oversight

Motor Vehicle Safety: NHTSA Should Resume Its Support of State Periodic Inspection Programs

Published by the Government Accountability Office on 1990-07-05.

Below is a raw (and likely hideous) rendition of the original report. (PDF)

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GAO

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.I II I \ 1!WO

                                                      MOTOR VEHICLE
                                                      SAFETY
                                                      NHTSA Should
                                                      Resume Its Support of
                                                      State Periodic
                                                      Inspection Programs

                                                                                                              5
                                                                                                     I I
                                                                                                   141954




                                               General Accounting olYke unless specifically
                                               approved by the Office of Cmqressional
                                           ~t~Fh!~:,
      United States
GAO   General Accounting Office
      Washington, D.C. 20648

      Resources, Community, and
      Economic Development Division

      B-223736

      July 6, 1990

      The Honorable John D. Dingell
      Chairman, Subcommittee on Oversight
        and Investigations
      Committee on Energy and Commerce
      House of Representatives

      Dear Mr. Chairman:

      In response to your July 26, 1989 request, this report evaluates the Department of
      Transportation’s exercise of its state motor vehicle inspection program responsibilities
      through its National Highway Traffic Safety Administration (NHTSA).

      We focused our work on determining whether (1) NHTSA'S 1989 report accurately represented
      the safety benefits of state inspection programs, (2) available evidence indicates that state
      inspection programs reduce accident rates, and (3) NHTSA appropriately carried out its
      legislative responsibilities toward inspection programs. Our report recommends that NHTSA
      resume its support of periodic inspection programs, and we provide suggestions for ways
      NHTSA can promote these programs.

      As agreed with your office, unless you publicly announce its contents earlier, we plan no
      further distribution of this report until 30 days from the date of this letter. At that time, we
      will send copies of this report to the Secretary of Transportation, the Administrator of
      NHTSA, and other interested parties.

      This work was performed under the direction of Kenneth M. Mead, Director, Transportation
      Issues, who can be reached at (202) 2751000. Other major contributors to the report are
      listed in appendix III.

      Sincerely yours,




      J. Dexter Peach
      Assistant Comptroller General
l3xecutive Summq


              Currently, 21 states and the District of Columbia require annual inspec-
Purpose       tions of motor vehicles as part of their safety programs. The effective-
              ness of periodic motor vehicle inspection programs has been a
              controversial issue for many years. In 1988, the Congress requested the
              Department of Transportation’s (DOI') National Highway Traffic Safety
              Administration (NHTSA) to study state inspection programs to determine
              whether they improve highway safety. NHTSA'S report, issued in 1989,
              concluded that periodic inspection programs reduce the number of
              poorly maintained vehicles on the highways, but that available data did
              not conclusively demonstrate that inspection programs significantly
              reduced accident rates.

              NHTSA'S  report has been criticized by various industry groups for not
              accurately representing the safety benefits of inspection programs.
              Because of this, the Chairman, Subcommitee on Oversight and Investiga-
              tions, House Committee on Energy and Commerce, asked GAO to evaluate
              NHTSA'S 1989 report to determine whether: (1) NHTSA'S report accurately
              represented the safety benefits of state inspection programs, (2) avail-
              able evidence indicated that state inspection programs reduce accident
              rates, and (3) NHTSA carried out its legislative responsibilities toward
              inspection programs.


              The Highway Safety Act of 1966 required the Secretary of Transporta-
Background    tion to prescribe uniform standards for mandatory state highway safety
              programs. A state not complying with the standards could lose its
              highway safety grant funds and 10 percent of its federal highway con-
              struction funds. From 1967 to 1972, DOT issued 18 standards, 1 of which
              required states to conduct periodic motor vehicle inspections. In 1973,
              NHTSA issued specific inspection standards, such as minimum thickness
              of brake linings and minimum tire tread depth.

              By 1975, 31 states and the Distict of Columbia had periodic inspection
              programs. NHTSA attempted to use funding sanctions against certain
              states to enforce the adoption of its various highway safety standards.
              However, the Congress passed the Highway Safety Act of 1976, deleting
              the Secretary’s authority to withhold highway construction funds and
              providing that state safety programs could be approved without
              meeting every program standard. Subsequently, 10 states repealed their
              periodic inspection programs.

              For its 1989 report, NHTSA considered most of the available studies of
              periodic inspection programs and also did five analyses of accident data


              Page 2                             GAO/RCED99-176Periodic Inspection Programe
                   Faecutive Summary




                   available at its headquarters. NHTSA acknowledged that all of these
                   studies, including NHTSA'S analyses, had limitations of scope, age, and/or
                   methodological completeness.


                   NIITSA'S 1989 report accurately concluded that state periodic inspection
Results in Brief   programs reduce the number of poorly maintained vehicles on the high-
                   ways. This is an important finding because vehicles with worn or defec-
                   tive brakes, tires, lights, or other safety-related components are a
                   hazard to both their owners and other motorists. For example, Virginia
                   officials provided data showing that 25 percent of the vehicles inspected
                   in 1986 had brake defects. NHTSA'S report showed that accidents
                   involving vehicle defects occur less often in states requiring periodic
                   inspections.

                   NHTSA'S   conclusion that available data did not conclusively demonstrate
                   that inspection programs significantly reduced accident rates was based
                   primarily on two analyses it did using fatal accident data. Whether
                   intended or not, this conclusion conveyed undue skepticism about the
                   effectiveness of inspection programs and tended to overshadow NHTSA'S
                   finding that inspection programs improve the safety condition of vehi-
                   cles. GAO found that analyses such as NHTSA'S have been hindered by the
                   limitations of available accident data. For example, police acci,dent
                   reports are the source of most data, but they tend to understate the
                   number of accidents in which defective vehicle components contributed
                   to the cause. If driver error or poor road conditions are involved, the
                   investigating officer may not recognize that worn brakes or tires helped
                   cause or aggravate the accident.

                   GAO considered all the studies and analyses in NHTSA'S report and others
                   not discussed by NHTSA. Even taking into account the limitations of indi-
                   vidual studies, their relative consistency in pointing to a safety benefit
                   from periodic inspection justifies a conclusion that these programs
                   reduce accident rates. The magnitude of accident reduction could not be
                   determined because of the data limitations and the methodological
                   problems encountered by those who have studied it.

                   While NHTSA met its obligations under the 1966 legislation to prescribe
                   standards for state inspection programs, the agency did not promote
                   periodic inspection after the Congress restricted its sanction authority in
                   1976. Although NHTSA was not required after 1976 to support periodic
                   inspection, it could have sponsored research and provided information
                   to help states initiate and improve programs. Recently, NHTSA indicated


                   Page 3                              GAO/RCEDQO-175Periodic Inspection Programs
                           Executive Summary




                           a renewed interest in inspection programs and is considering how it can
                           provide such assistance to states. GAO is making a recommendation in
                           this regard.



Principal Findings

NHTSA’s Report Indicated   NHTSA  reviewed eight studies which compared the condition of safety-
That Inspection Programs   related components on vehicles subject to periodic inspection with those
                           in non-inspection jurisdictions. All eight showed that vehicles subject to
Have Safety Benefits       periodic inspection had fewer defective components than those in areas
                           not requiring inspections. For example, one study in the 1970s found
                           that Pennsylvania, when it still required semiannual inspections, had 46
                           percent fewer vehicles with defective equipment than California, which
                           used random police inspections. NHTSA'S report also indicated that
                           existing state programs vary in their reliability in detecting and cor-
                           recting vehicle defects.

                           NHTSA'S  report also discussed an Indiana study that investigated 420
                           accidents in depth and found that 12.6 percent were caused or aggra-
                           vated by defective or worn vehicle equipment. Several other studies,
                           including two by NHTSA itself, showed that accidents involving worn or
                           defective equipment occurred less in states requiring periodic
                           inspections.

                           Studies that have compared fatal accident rates between inspection and
                           non-inspection states have found mixed results in trying to estimate the
                           effect of inspection programs. These studies have been hindered by the
                           limitations of available accident data and the difficulty of accounting
                           for the various factors that can affect accident rates. Also, fatal acci-
                           dents are less than 1 percent of all accidents and are not typical of the
                           universe of accidents.

                           NHTSA  found that fatal accident rates were about the same in inspection
                           states as in non-inspection states. NHTSA also compared total accidents in
                           four inspection states with those in six non-inspection states, and con-
                           cluded that there was no significant difference in accident rates. In fact,
                           the reported accident rate was 17 percent lower in the inspection states,
                           but NHTSA questioned the comparability of the data and adjusted it to
                           largely eliminate the difference between the two groups of states. For
                           several reasons discussed in this report, GAO did not agree with NHTSA'S


                           Page 4                              GAO/RCED-90-1’75
                                                                              Periodic Inspection Programs
                          Executive Summary




                          adjustment, and considered the 17-percent difference to be further evi-
                          dence that inspection programs reduce accident rates.

                          Taken together, the studies discussed in NHTSA'S report as well as several
                          other studies identified by GAO indicated that inspection programs
                          reduce accident rates. These studies included estimates of accident
                          reduction ranging from less than 1percent to as high as 27 percent. The
                          actual magnitude of the reduction is unknown. GAO agrees with NHTSA
                          that all of the studies had limitations either of scope, age, or method-
                          ological completeness. Thus, while the large majority of studies point to
                          a safety benefit from inspection programs, they do not provide a reliable
                          basis for judging how much effect the programs have on accident rates.


NHTSA Intends to Resume   NHTSA officials told GAO that the agency intends to resume its support of

Its Support of Vehicle    periodic vehicle inspection. The contribution these programs make to
                          highway safety provides a basis for NHTSA'S support of such programs.
Inspection Programs       After reviewing NHTSA'S actions under the 1966 and subsequent legisla-
                          tion, GAO concluded that the agency met its legislative obligations. As
                          mandated, NHTSA issued a standard requiring states to inspect vehicles
                          at least annually, and in 1973 issued specific standards for vehicle
                          inspection. NHTSA officials acknowledged, however, that the agency did
                          not promote inspection programs after the Congress in 1976 deleted
                          NHTSA'S authority to withhold highway construction funds. Under the
                          law, NHTSA was not required to support inspection programs, but it could
                          have continued to promote and help improve programs by sponsoring
                          research and providing information to states on effective ways to
                          operate programs.


                               is recommending that the Secretary of Transportation direct NHTSA
Recommendation            GAO
                          to support state periodic motor vehicle inspection programs through
                          such actions as (1) sponsoring research, (2) assisting inspection states to
                          share their experiences and adapt to changing automotive technology,
                          and (3) promoting public awareness of the need to properly maintain the
                          safety-critical components of vehicles.


                          As requested, GAO did not obtain official agency comments on a draft of
Agency Views              this report. However, GAO discussed the report’s contents with NHTSA
            Y             officials, and they generally agreed with GAO'S findings. GAO incorpo-
                          rated their clarifying comments as appropriate. These officials said that
                          NHTSA welcomes suggestions for ways to promote and improve inspec-
                          tion programs.


                          Page 5                              GAO/RCED-90-176Periodic Inspection Programs
Contents


Executive Summary                                                                                               2

Chapter 1                                                                                                      8
Background                   NHTSA’s Involvement in Periodic Motor Vehicle
                                 Inspection Programs
                                                                                                               8

                             Objectives, Scope, and Methodology                                                11

Chapter 2
NHTSA’s 1989 Report NHTSA’s    Report Indicated That Inspection Programs
                         Have Safe
and Other Data Show Additional Stu UltjJIJ”LzUAJLU33~U vyLYll IUAfi1.7”
That Periodic            Indicated That Periodic Inspection Programs Reduce
                        Accidents
Inspection Programs
ReduceAccident Rates Conclusion
Chapter 3                                                                                                  21
NHTSA Intends to             NHTSA Met Its Original Obligations but Has Not Actively
                                 Supported Vehicle Inspections Since 1976
                                                                                                           21
ResumeIts Support of         Inspection Programs Could Be More Effective                                   22
Vehicle Inspection           Conclusions                                                                   23
                             Recommendation                                                                24
Programs                     Agency Views                                                                  24

Appendixes                   Appendix I: States Requiring Periodic Vehicle Inspections                     26
                             Appendix II: Principal Studies Discussed in NHTSA’s                           27
                                 Report
                             Appendix III: Major Contributors to This Report                               33

Figures                      Figure 2.1: Defective Equipment Reported on Vehicles                          16
                                  Involved in Accidents, 1984-86
                             Figure 2.2: Defective Equipment Reported on Vehicles                              17
                                  Involved in Fatal Accidents, 1985-87




                             Page 0                             GAO/RCEDSO-175Periodic Inspection   Programs
    Contents




    Abbreviations
*
    DOT        Department of Transportation
    GAO        General Accounting Office
    NHTSA      National Highway Traffic Safety Administration


    Page7                               GAO/RCED-90-17sPeriodic Inspection Program
Chapter 1

Background


                      In order to reduce the toll of highway accidents, the Congress created
                      the National Highway Traffic Safety Administration (NHTSA) within the
                      Department of Transportation’ (DCT) to enforce federal motor vehicle
                      safety standards, sponsor safety research and development, and sup-
                      port state highway safety programs.

                      In 1966, traffic accidents killed 50,894 persons in the United States. In
                      1988, the traffic death toll had decreased to 47,093. The number of
                      vehicle miles traveled, estimated at 926 billion in 1966, had increased to
                      over 2 trillion by 1988. Measured in terms of vehicle miles traveled, the
                      fatality rate in 1988 was 58 percent lower than in 1966. Many factors
                      have contributed to this decline, including improved vehicles, improved
                      highways, and programs to raise the safety consciousness of drivers.
                      NHTSA has estimated that one major initiative, safety belts, saved 4,500
                      lives in 1988. Among the many programs intended to reduce the number
                      and severity of accidents are the requirements in 21 states and the Dis-
                      trict of Columbia for periodic inspection of motor vehicle brakes, tires,
                      steering, and other safety-related components.


                      The Highway Safety Act of 1966 (P.L. 89-564) and the National Traffic
NHTSA’s Involvement   and Motor Vehicle Safety Act of 1966 (P.L. 89-563) both established
in Periodic Motor     responsibilities for the Secretary of Transportation.” The National
Vehicle Inspection    Traffic Safety Bureau (later NHTSA) was created to administer these acts
                      on behalf of the Secretary.
Programs
                      The first act required the Secretary to prescribe uniform standards for
                      mandatory state highway safety programs. The Secretary was required
                      to approve each state’s program and withhold highway safety grant
                      funds and 10 percent of highway construction funds from states not
                      complying with the program standards. The act specifically mentioned
                      vehicle inspection among the potential subjects for state program stan-
                      dards. The second act required the Secretary to establish safety stan-
                      dards for new vehicles, and standards for the inspection of vehicles in
                      use.



                      ‘The agency was originally called the National Highway Safety Bureau and was under the Depart-
                      ment of Commerce. It moved to the Department of Transportation (when that agency began opera-
                      tions on Apr. 1, 1967), where it was under the Federal Highway Administration until it was
                      established as a separate agency within the Department in 1970.

                      ‘The legislation actually referred to the Secretary of Commerce, but these responsibilities were trans-
                      ferred to the newly created Secretary of Transportation in 1967.



                      Page 8                                            GAO/RCED-90-176Periodic Inspection Programs
                           Chapter 1
                           Background




NHTSA’s Issuance and       In carrying out the Highway Safety Act of 1966, DOT issued 18 standards
Enforcement of State       for state highway safety programs from 1967 through 1972. The first
                           standard required each state to have a program for periodically
Safety Program Standards   inspecting all registered vehicles or an experimental, pilot, or demon-
                           stration program approved by the Secretary. NIITSA officials said that in
                           1973, under pressure from a court order, the agency established the spe-
                           cific standards for inspecting vehicles required by the National Traffic
                           and Motor Vehicle Safety Act of 1966. These standards applied to
                           brakes, tires, wheels, and steering and suspension components, and
                           included such items as minimum brake lining thickness and tire tread
                           depth.

                           In response to the DUT requirements, 11 states adopted periodic inspec-
                           tion laws between 1967 and 1972, bringing the total to 31 plus the Dis-
                           trict of Columbia. In 1975, NIITSA prepared to use the authorized funding
                           sanctions to enforce state compliance with safety program standards,
                           particularly those involving blood alcohol content for drunk driving,
                           motorcycle helmet use, and periodic vehicle inspection. The sanction
                           process was suspended when the Congress passed the Highway Safety
                           Act of 1976, deleting the Secretary’s authority to enforce the safety pro-
                           gram standards by withholding highway construction funds. The act
                           also specified that the Secretary should not “require compliance with
                           every uniform standard, or with every element of every standard, in
                           every state.”


NHTSA’s Reaction to the    While the 1976 act did limit NIII'SA'S authority to require state program
Highway Safety Act of      activities, it did not eliminate the Secretary’s authority to approve state
                           highway safety programs and withhold highway safety program funds
1976                       from states not having approved programs. And it did not repeal the
                           statement in the National Traffic and Motor Vehicle Safety Act of 1966
                           that “it is the policy of Congress to encourage and strengthen the
                           enforcement of State inspection of used motor vehicles.” Nonetheless,
                           em adopted a policy that all highway safety program standards would
                           be optional and states could determine their own priorities. Dm reported
                           to the Congress in 1977 that it could not statistically demonstrate the
                           effectiveness of any of its 18 program standards, including periodic
                           vehicle inspections. DO?' stated: “This is not to say that the highway
                           safety program and the standards do not improve safety. Rather, this is
                           an admission of our inability to produce statistically verifiable data
                           which convincingly demonstrate what our common sense tells us.” Since
                           1977, NHTSA has not withheld highway safety funds from any state for



                           Page 9                              GAO/RCED-90-175Periodic Inspection Programs
                                                                                                                            ,-
                           Chapter 1                                                                                   ,
                           Background




                           noncompliance with a safety program standard.:’ Regarding periodic
                           inspection programs, NHTSA officials agreed that the agency stopped pro-
                           moting them after 1976.

                           From 1976 through 1982, 10 states repealed their periodic inspection
                           laws, including 7 of the states that adopted their laws in response to the
                           Highway Safety Act of 1966. Currently, 21 states and the District of
                           Columbia require annual motor vehicle safety inspections. All but three
                           of these programs predate the 1966 act, with some going back to the
                           1930s and one to 1929. These states are primarily on the eastern sea-
                           board or the Gulf Coast. (See app. I.) New Jersey, Delaware, and the
                           District operate facilities which perform the inspections. The remaining
                           19 states license private garages to do inspections, monitored by the
                           state police or another state agency. For a fee, the mechanics inspect the
                           condition of brakes, tires, steering components, lights, and other safety-
                           related equipment on the vehicles. Vehicles not meeting state standards
                           must be repaired and reinspected. Federal funds are not used to support
                           state inspection operations.


NHTSA Required to Report   We reported in 1977 that many states were reluctant to adopt periodic
on Inspection Program      inspection programs because they were not convinced of the benefits of
                           such programs.4 Therefore, we recommended that NHTSA undertake pri-
Effectiveness              ority research to demonstrate program effectiveness. NIITSA did not,
                           however, undertake any new research on the effects of inspection
                           programs.

                           In 1988, the Congress requested that NIITSA study existing state inspec-
                           tion programs and determine whether they reduce the number of poorly
                           maintained vehicles on the highway and help reduce accident rates.
                           NIWSA reviewed prior studies, surveyed the current status of vehicle
                           inspection programs, and performed analyses using data available at
                           NIIWA headquarters. NHTSA also held public hearings and solicited com-
                           ments from state officials and other interested persons. NIITSA reported
                           in 1989” that periodic inspection programs reduce the number of poorly



                           “In 1987, the Congress changed the highway safety program standards to guidelines.

                           “Effectiveness of Vehicle Safety Inspections Neither Proven Nor Ilnproven (CED-78-18, Dec. 20,
                           1977), pp. 20-22.
                           “Study   the Effectiveness of State Motor Vehicle Inspection Programs. NIITSA (Washington, D.C.:
                           A?g. 1989).



                           Page 10                                         GAO/RCED-90-176Periodic Inspection Programs
                        Chapter 1
                        Background




                        maintained vehicles on the highways, but reported that it could not con-
                        clusively demonstrate that the programs significantly reduce accident
                        rates.


                        Various organizations have criticized NHTSA for alleged shortcomings in
Objectives, Scope,and   its 1989 report and for its lack of support for periodic vehicle inspec-
Methodology             tion Consequently, the Chairman, Subcommittee on Oversight and
                        Investigations, House Committee on Energy and Commerce, asked us to
                        assess whether NHTSA has adequately carried out its vehicle inspection
                        responsibilities and what safety benefits can be attributed to such
                        programs.

                        In agreement with the Chairman’s office, we focused our work on deter-
                        mining whether: (1) NHTSA'S 1989 report accurately represented the
                        safety benefits of state inspection programs, (2) available evidence indi-
                        cated that state inspection programs reduce accident rates, and (3)
                        NHTSA appropriately carried out its legislative responsibilities toward
                        inspection programs.

                        To carry out the first objective, we reviewed NHTSA'S 1989 report and
                        discussed it with the NHTSA personnel who prepared it. We involved
                        methodological experts on our staff in assessing NHTSA'S analyses of
                        available data. We reviewed some of the prior studies cited by NHTSA,
                        most of which were done before 1980, and in other cases, accepted
                        NIITSA'S summarization of them. We considered whether, given the infor-
                        mation contained in NHTSA'S report, we would have arrived at similar
                        conclusions.

                        For the second objective, we reviewed comments submitted to NHTSA by
                        states and other interested parties to determine if there was other infor-
                        mation or studies that NHTSA did not consider in its 1989 report. We also
                        reviewed an available literature search and asked officials from NHTSA,
                        states, and interested organizations if they were aware of other relevant
                        studies or analyses. From this effort, we identified four studies not dis-
                        cussed by NHTSA in arriving at its conclusions. We used this additional
                        information along with the studies discussed by NHTSA to assess the rela-
                        tionship between periodic vehicle inspection programs and accident
                        rates.

                        For the third objective, we reviewed legislation, regulations, and other
                        documents relating to NHTSA'S safety programs and discussed their
                        implemention with officials of NHTSA; the American Association of Motor


                        Page 11                             GAO/RCED-90-176Periodic Inspection Programs
                                                                   ‘4


Chapter 1
Background




Vehicle Administrators; and the Coalition for Safer, Cleaner Vehicles.
Specifically, we considered whether NHTSA met its minimum obligations
under the 1966 legislation and whether it adopted an appropriate role in
response to the 1976 legislative changes.

We also considered whether NHTSA should encourage periodic inspection
programs and how the programs could be improved, As requested by
the Chairman, we interviewed officials of interested organizations and
visited states with inspection programs (New Jersey, Pennsylvania, and
Virginia) as well as states without them (Florida, Indiana, and Ohio). In
Indiana and Florida, we discussed the reasons why previous inspection
laws were repealed. We also attended a conference on vehicle inspection
at which officials from a number of other states participated.

We conducted our audit work between September 1989 and February
1990 in accordance with generally accepted govern-tent auditing stan-
dards, We discussed the report’s contents with NHTSA officials and incor-
porated their clarifying comments as appropriate. However, as
requested, we did not obtain offical NHTSA comments on a draft of this
report.




Page 12                             QAO/IUXD4W176 Periodic Impection Progmmii
Chapter 2

NHTSA’s 1989 Report and Other Data Show
That Periodic Inspection Programs Reduce
Accident Rates
                       NHTSA'S  1989 report accurately concluded that state periodic inspection
                       programs reduce the number of poorly maintained vehicles on the high-
                       ways. This is an important finding because vehicles with worn or defec-
                       tive brakes, tires, lights, or other safety-related components are a
                       hazard to both their owners and other motorists. NHTSA'S report also
                       showed that accidents involving vehicle defects occur less often in states
                       requiring periodic inspections.

                       NHTSA'S   conclusion that available data did not conclusively demonstrate
                       that inspection programs significantly reduced accident rates was based
                       primarily on two analyses it did using fatal accident data. Whether
                       intended or not, this conclusion conveyed undue skepticism about the
                       effectiveness of inspection programs and tended to overshadow NHTSA'S
                       finding that inspection programs improve the safety condition of vehi-
                       cles. Analyses such as NHTSA'S have been hindered by the limitations of
                       available accident data. We considered all the studies and analyses in
                       NHTSA'S report and others not discussed by NHTSA. Even taking into
                       account the limitations of individual studies, their relative consistency
                       in pointing to a safety benefit from periodic inspection justifies a conclu-
                       sion that these programs reduce accident rates. The magnitude of acci-
                       dent reduction could not be determined because of the data limitations
                       and the methodological problems encountered by those who have
                       studied it.


                                 1989 report demonstrated that periodic inspection programs
NHTSA’s Report         NHTSA'S
                       improve the condition of the safety-related components of vehicles sub-
Indicated That         ject to inspection. The report also contained consistent evidence that
Inspection Programs    fewer accidents involving defective or worn vehicle equipment occur in
                       states requiring inspections. While this would seem to be persuasive evi-
Have Safety Benefits   dence that the programs reduce overall accident rates, comparisons of
                       fatal accident rates do not always show such an effect. Unfortunately,
                       most comparisons have been confined to fatal accident data because of
                       their availability and reliability. However, fatal accidents represent less
                       than 1 percent of all accidents and may not be the type of accidents
                       most affected by defective vehicle equipment. Also, it is difficult in any
                       comparison of accident rates to control the various other factors that
                       can influence them.

                       In assessing NHTSA'S report, we considered all the evidence and noted
                       that most of the studies indicated a safety benefit from inspection pro-
                       grams. We believe NHTSA may have focused too much on its own compar-
                       isons of state accident rates, considering the limitations of such


                       Page 18                              GAO/RCEDQO-176Periodic Inspection Programs
                                                                                                                ,
                            Chapter 2                                                                       ‘
                            NIIWA’a 1989Report and Other Data Show
                            That Periodic Inspection Program Reduce
                            Accident Rates




                            comparisons. While NHTSAmay not have intended to draw negative con-
                            clusions about the effectiveness of inspection programs, it did seem to
                            place emphasis on the analyses that did not support the programs. This
                            left the impression that NHTSAwas skeptical of the benefit of inspection
                            programs.


NHTSA’s Report Showed       To determine whether periodic inspections improve vehicle condition,
That Inspection Programs    NHTSAreviewed eight studies which compared the condition of safety-
                            related components on vehicles subject to periodic inspection with those
Improve Vehicle Condition   in non-inspection jurisdictions. All eight studies showed that vehicles
                            not subject to periodic inspection had more defective components than
                            those in areas requiring inspections. For example, Tennessee found in
                            the 1970s that vehicles in Memphis and Chattanooga, which required
                            inspections, had fewer safety defects than those in Knoxville, which did
                            not. As another example, two NHTSA-sponsored studies in the early
                             1970s compared results from diagnostic centers in 10 states. The three
                            states with the lowest defect rates were states that required periodic
                            inspections. Pennsylvania, which at that time required semiannual
                            inspections, had 45 percent fewer vehicles with defective equipment
                            than California, which used random police inspections. These studies
                            indicated that semiannual inspections were more effective than annual
                            inspections, which in turn were more effective than random inspections.
                            NHTSAconcluded from its review of these eight studies that periodic
                            inspection programs limit the number of poorly maintained vehicles on
                            the highways.


NHTSA’s Report              If periodic inspection programs are effective, they should reduce the
Demonstrated That           number of accidents caused or aggravated by worn or defective vehicle
                            equipment. To determine if this was so, NHTSAreviewed a study done in
Inspection Programs         Indiana on the causes of accidents, and three studies comparing the rate
Reduce Accidents Caused     of vehicle defects cited in accident reports. NHTSAalso performed two
by Vehicle Defects          data analyses comparing accident reports from inspection and non-
                            inspection states.

                            NHTSAsponsored a study in Monroe County, Indiana, in the early 1970s
                            to determine the causes of traffic accidents. As part of that study, large,
                            multidisciplinary teams conducted in-depth follow-up investigations of
                            420 accidents. The study concluded that defective vehicle components
                            were the sole cause or a contributing cause of 12.6 percent of the acci-
                            dents (4.5 percent definite, 8.1 percent probable). Failure or



                            Page 14                                   GAO/RCED-90-175Periodic Inspection Programs
chapter 2
NEITSA’s1989Report and Other Data Show
That Periodic Inspection Progranu Reduce
Accident Rates




underperformance by brakes and tires were the most commonly noted
deficiencies that contributed to accidents.

The three other studies of vehicle-defect involvement in accidents all
indicated that periodic inspection programs reduce accidents caused by
vehicle defects. For example, a 1975 NHTSA study cited data showing
that reported vehicle-defect accidents declined from 12 to 4 percent of
all accidents in Texas and from 6.1 to 2.6 percent in rural Nebraska in
the years following implementation of inspection programs. Another of
these studies found a lower rate of vehicle-defect accidents on the Penn-
sylvania Turnpike than on the Indiana and Ohio Turnpikes during a
period when Pennsylvania was the only one of these states requiring
inspections.

NHTSA  did two analyses of computerized accident reports to determine
how often vehicle equipment failures were noted on vehicles involved in
accidents. One involved all accidents in four states and the other
involved fatal accidents in all states. In the four-state study, NHTSA
found that vehicle equipment failures were reported on about 1 percent
of the vehicles involved in accidents in the inspection states (Penn-
sylvania and Texas) and about 2 percent in the non-inspection states
(Maryland and Washington). As shown in figure 2.1, the difference
between the states was greater for older vehicles than for newer ones,
which indicates that inspection programs have more effect on older
vehicles. This confirmed NHTSA'S hypothesis that the effect of inspection
programs would be most evident for older vehicles.




Page 15                                    GAO/RCED-SO-175
                                                         Periodic Inspection Programs
                                               Chapter 2
                                               NHTSA’e 1989Report and Other Data Show
                                               That Periadic Inspection ProgramsReduce
                                               Accident Rates




Figure 2.1: Defective Equipment Reported on Vehicles Involved in Accidents, 1984-86
                                       Percent Accident-Involved        Vehicles
                                  /I




                              0          1     2       3       4    S        6       7      8       9     10
                                                           Vehicle Age (Yrs.)

                                                   m   Inspection        m       Non-Inspection


                                               Source: NHTSA


                                               NHTSA'S second analysis, using nationwide fatal accident data from 1985
                                               through 1987, also showed that defects were noted on vehicles involved
                                               in fatal accidents less often in inspection states than in non-inspection
                                               states. Once again, as shown in figure 2.2, NHTSA found that the differ-
                                               ence between inspection and non-inspection states widened for older
                                               vehicles. Thus, NHTSA'S analysis of fatal accidents in all states confirmed
                                               its four-state analysis of total accident data.




                                               Page 16                                            GAO/RCED-90-176Periodic Inspection Programs
                                              Chapter 2
                                              NIiT8A’s 1989Report and Other Data Show
                                              That Periodic Inspection ProgramsReduce
                                              Accident Rates




Figure 2.2: Defective Equipment Reported on Vehicles Involved in Fatal Accidents, 1985-87
                                 Peroent Fatal Accident-Involved      Vehicles




                             0     1      2        3      4    5      6     7     8      9     10
                                                        Vehicle Age (Yrs.)



                                              Source: NHTSA


                                              NHT~A   considered the differences between the states too small to be of
                                              any practical significance. However, police accident reports may under-
                                              state the percentage of accidents caused by defective vehicle equipment.
                                              The Indiana study found that police officers did not identify all of the
                                              vehicle defects that contributed to the accidents studied. The Indiana
                                              researchers noted that police officers must try to determine who was
                                              legally responsible for an accident, and may not look further for causal
                                              relationships. As New York officials pointed out in comments to NHTSA,
                                              police officers are not mechanics, and their first concern at an accident
                                              scene must be the care of the injured and clearing the site of hazards.

Accident Rate                                 In addition to studying the role of vehicle defects in accidents, NHTSA
Comparisons Have Been                         also reviewed studies which compared accident rates (mostly fatal acci-
                                              dent rates) between inspection and non-inspection states. Fatal accident
Inconclusive Because of                       data are more readily available and more reliable, but fatal accidents
Data Limitations                              represent less than 1 percent of all accidents. On the other hand, total
                                              accident data are difficult to interpret because of different reporting
                     *                        practices among the states.

                                              Among eight studies NHTSA reviewed, six compared fatal accident rates
                                              between states with and without inspection programs. Three found


                                              Page 17                                   GAO/RCED-90-175Periodic   InspectionPrograms
Chapter 2
NHTSA’s 1999Report and Other Data Show
That Periodic hpection ProgramaReduce
Accident Rates




lower accident rates in states requiring periodic inspections, one found
higher rates, and two found inconclusive results. The remaining two
studies were done within single states. One of these, done in Huntsville,
Alabama, compared a sample of inspected vehicles with other vehicles
in Huntsville. The authors estimated that the inspected vehicles were
involved in 9-21 percent fewer accidents. The other, a historical study
done in New Jersey, compared total accident rates for a number of years
before and after the state’s adoption of an inspection program. Control-
ling for a number of other factors, the study estimated an accident
reduction of 23 percent from the state’s inspection program.

While each of the previous studies had limitations, taken together, they
suggested that periodic inspections reduce accident rates. However,
NHTSA did three data analyses comparing accident rates among the states
which produced apparently conflicting evidence. Two of these used fatal
accident data from 49 states and found fatal accident rates to be about
the same in inspection states as in non-inspection states. In the first of
these two analyses, a comparison by age of vehicle also showed little
difference, although vehicles 9-12 years old were more likely to be
involved in fatal accidents in states not requiring periodic inspection. In
the second analysis, NHTSA looked at fatal accidents involving 1976 vehi-
cles over an 1 l-year period, and did not find a trend favoring inspection
states as the vehicles got older.

NHTSA'S  third analysis of accident rates used state accident data files to
compare total accidents in four inspection states with those in six non-
inspection states. The inspection states showed a 17-percent lower acci-
dent rate than the non-inspection states. However, NHTSA doubted the
comparability of the data because it showed that relatively new vehicles
(O-21 months old) also had higher accident rates in the non-inspection
states. NHTSA assumed that newer vehicles have few defects and thus
should not have higher accident rates in non-inspection states.

NHTSA   adjusted the data from this analysis and largely eliminated the
difference between the two groups. NHTSA justified this in its report by
stating that the inspection states were not reporting as many accidents
because they had higher damage thresholds for reporting accidents than
the non-inspection states. We found the reverse to be true: the inspection
states in NHTSA'S sample had lower thresholds for reporting accidents
than the non-inspection states.

We also question NHTSA'S reason for adjusting the data. According to the
U.S. Department of Commerce, more than a third of new vehicles are


Page 18                                  GAO/RCED-90-176Periodic Inspection Programs
                           chapter2
                           NIi’JX3A’s1989Report and Other Data Show
                           That Periodic Inspection ProgramsReduce
                           Accident Rates




                           used for business purposes. Such vehicles may be driven 25,000 miles in
                           their first year, according to the American Automotive Leasing Associa-
                           tion They could develop problems with brakes, tires, or steering at an
                           early age, problems that an inspection program would identify. More-
                           over, older vehicles in non-inspection states may involve new vehicles in
                           more accidents than would occur if the older vehicles were subject to
                           periodic inspection.

                           NHTSA'S comparisons of accident rates are also limited by the fact that,
                           except for vehicle age, NHTSA did not control for other factors that can
                           influence state accident rates. We found, for example, that traffic den-
                           sity was higher in the inspection states. Motorists in these states trav-
                           eled 20 percent more per mile of roadway in 1988 than motorists in non-
                           inspection states.

                           NHTSA  also reviewed several studies that had attempted to estimate costs
                           and benefits of periodic inspection programs. The majority of these
                           studies, including NHTSA'S own 1975 study, indicated that the programs
                           were cost-effective. NHTSA questioned their assumptions, however, and                             ’
                           concluded that “none of the reviewed studies provide credible evidence
                           that current programs are cost-effective.” NHTSA officials told us they
                           did not do a new cost-benefit analysis for their report.


                           In addition to the information discussed in NHTSA'S report, we identified
Additional Studies Not     four other studies, all of which indicated an accident-reduction benefit
Discussedby NHTSA          from periodic inspection programs:
Also Indicated That        Florida officials provided us two studies showing that the percentage of
Periodic Inspection    l
                           accidents caused by vehicle defects decreased when periodic inspections
Programs Reduce            were begun, and increased when the inspection law was repealed.
Accidents              .   In comments submitted to NHTSA for its report, the Illinois Department of
                           Transportation discussed the effect of terminating the semiannual
                           inspection of pickup trucks and vans in 1984. It reported a sharp
                           increase in the rate of accidents and injuries involving pickup trucks and
                           a small increase for vans in the 3 years following repeal.
                       .   A study done at Rutgers University used 12 different variables in a
                           regression analysis of fatal accident data from 1979.’ The author con-
                           cluded that inspection programs can reduce fatal accident rates by a sig-
                           nificant amount.

                           ‘Peter D. Loeb, “The Determinants of Automobile Fatalities With Special Consideration to Policy
                           Variables,” Journal of Transport Economics and Policy, Sept. 1987, pp. 279-287.



                           Page 19                                          GAO/RCEDdO-175Periodic Inspection Programs
                                                                                              .
             Chapter 2
             NIi’IWA’s 1989Report and Other Data Show
             That Periodic Inspection ProgramsReduce
             Accident Rates




             A large majority of the studies NHTSA reviewed, and four additional ones
Conclusion   that we identified, indicated that inspection programs improve highway
             safety. We believe that when all the studies and analyses are considered
             together, even taking into account their individual limitations, their rela-
             tive consistency justifies a conclusion that periodic inspection programs
             reduce accident rates. None of the studies, however, produced a reliable
             estimate of the magnitude of accident reduction that can be expected
             from an inspection program. Various studies have placed it as low as
             less than 1 percent to as high as 27 percent. While it would be reason-
             able, on the basis of current evidence, for NHTSA to encourage the adop-
             tion of periodic inspection programs, states would have a better basis
             for considering such programs if NHTSA sponsored a carefully controlled
             research project to estimate their accident-reduction potential. Ideally,
             such research would follow the accident experience of a randomly
             selected group of inspected vehicles and a control group of vehicles not
             subject to inspection.

             We discussed our interpretation of the data with NHTSA officials respon-
             sible for the 1989 report, who said that their views are now close to
             ours. According to these officials, NHWA agrees that periodic inspection
             programs contribute to highway safety and should be supported.




             Page 20                                    GAO/RCED-90-175Periodic Inspection Programs
Chaoter 3

NHTSA Idends to ResumeIts Support of
Vehicle Inspection Programs

                         NHTSA met its obligations under the 1966 legislation to prescribe uniform
                         standards for state inspection programs. However, when the Congress
                         restricted its sanction authority in 1976, the agency chose not to con-
                         tinue promoting vehicle inspection programs. Some states have recently
                         considered initiating or reinstating inspection programs. It also appears
                         that inspection programs could be improved to enhance their contribu-
                         tion to traffic safety. NHTSA could promote and help improve inspection
                         programs by sponsoring research and providing information to states on
                         effective ways to operate inspection programs.


                         After reviewing the history of NHTSA actions under the 1966 legislation,
NHTSA Met Its            we conclude that NHTSA met its legislative obligations. As required by
Original Obligations     the Highway Safety Act of 1966, NHTSA issued standards for state
but Has Not Actively     highway safety programs, including a requirement that states inspect
                         motor vehicles at least annually. In 1973, NHTSA complied with a require-
Supported Vehicle        ment in the National Traffic and Motor Vehicle Safety Act of 1966 by
Inspections Since 1976   issuing specific standards for vehicle inspection. NHTSA was prepared to
                         enforce its safety program standards through federal funding sanctions
                         until the Congress deleted its authority to withhold highway construc-
                         tion funds in the Highway Safety Act 1976 and provided that state
                         safety programs could be approved without meeting every program
                         standard.

                         NHTSA  officials acknowledged that after 1976, the agency did not con-
                         tinue promoting vehicle inspection programs. NHTSA sponsored only one
                         more piece of original research: a study in Idaho that showed that the
                         condition of vehicles’ brakes, steering, and suspension deteriorated after
                         inspections were discontinued in the state in 1977. In 1978, NHTSA abol-
                         ished the office responsible for vehicle inspection.

                         NHTSA'S  withdrawal from the area of periodic inspection may have
                         reflected its earlier reservations about inspection programs. As early as
                         1972, NHTSA testified before the Senate Commerce Committee that it was
                         skeptical about the effectiveness of vehicle inspection programs. While
                         acknowledging that four studies from the 1960s had shown positive cor-
                         relations between inspection programs and lower traffic fatality rates,
                         NHTSA said that more recent data did not support such a relationship. It
                         said that an analysis with more variables was needed to determine
                         whether inspection programs reduce fatalities. NHTSA'S subsequent
                         actions, issuing vehicle-in-use inspection criteria and beginning the sanc-
                         tion process to enforce safety program standards, were taken under
                         pressure from court orders.


                         Page 21                             GAO/RCED-90-176Periodic Inspection Programs
                      chapter 3
                      NIfBA Intends to ResumeIts Support of
                      Vehicle Inspection Programs




                      NHTSA  officials believe their withdrawal from the area was supported by
                      comments they received from states in 1981. The Congress had directed
                      NHTSA to determine by rulemaking which of its 18 state safety programs
                      should be eligible for continued federal funding. When vehicle inspec-
                      tion was not one of the programs the states identified, NHTSA assigned it
                      to the category of non-priority programs. A NHTSA official commented
                      recently that the agency may have misinterpreted this response, since
                      inspection programs are generally self-supporting and do not require
                      federal funds.

                      Of the 11 states that initiated periodic inspection programs from 1967
                      through 1969,7 repealed their programs after NHTSA'S authority to with-
                      hold highway construction funds was deleted by the Highway Safety
                      Act of 1976. No states have initiated mandatory safety inspection pro-
                      grams since 1969. Florida and Colorado officials told us that safety
                      testing may be reinstated in the near future, while Connecticut has initi-
                      ated demonstration safety inspection facilities. Michigan’s written com-
                      ments for NHTSA'S 1989 report indicated a possible interest in starting a
                      periodic safety inspection program. In Missouri, on the other hand, the
                      state’s inspection program has been questioned in the state legislature.

                      Several state officials told us that NHTSA could be helpful by sponsoring
                      research to test new technologies and determine the most effective
                      approaches to vehicle inspection. They also said there is a need to dis-
                      seminate information on state program experiences. For example, Penn-
                      sylvania and New Jersey officials said that information on the hazards
                      of modified (raised) vehicles would be useful to many states. Other
                      states might also profit from New Jersey’s approach of using its inspec-
                      tion procedure to check drivers’ licenses, registrations, license plates,
                      and mandatory insurance coverage.


                      As NHTSA pointed out in its report, existing state inspection programs
Inspection Programs   vary in their effectiveness. For example, Pennsylvania allows its
Could Be More         licensed private garages to charge one-half hour of shop labor for an
Effective             inspection and requires removal of two wheels and a road test for brake
                      inspection. Pennsylvania rejects about 17 percent of its vehicles for
                      brake problems. Virginia requires its licensed private garages to pull one
                      wheel but some pull two anyway. Virginia’s stations found a 25-percent
                      deficiency rate for brakes. By improving its monitoring of stations, Vir-
          *I
                      ginia raised its overall vehicle rejection rate from 22 percent in 1982 to
                      34 percent in 1986, and recorded a 48-percent decline in accidents that it
                      attributed to vehicle defects over the same period. New Jersey charges


                      Page 22                                 GAO/RCED90-175Periodic Inspection Programs
              Chapter 3
              NHTSA Intends to ResumeIts Support of
              VeNcle Inspection Programs




              $2.50 and takes about 5 minutes to move a vehicle through its state-
              operated safety lanes, including a brake test on an old style of platform
              tester. New Jersey does not pull wheels and rejects about 12 percent of
              vehicles for brake problems (including the parking brake).

              Some officials believe that more effective and efficient testing can be
              achieved with the application of new technology. For example, Florida
              has contracted with private companies to build and operate facilities for
              its required emissions testing. Each facility must include one lane which
              offers free voluntary safety tests using modern equipment for detecting
              the wear of brakes, steering linkage, and alignment. Florida officials
              hope to build public support for reinstatement of periodic safety inspec-
              tions. Connecticut, which does not require safety inspections, has a pilot
              project to demonstrate the operation of safety inspection facilities using
              modern testing equipment.

              For states which rely on private garages to perform inspections, vig-
              orous monitoring and adequate fees are important for an effective pro-
              gram. Studies have shown that lax inspections are more often a problem
              than unneeded repairs. Indiana and Colorado officials told us that public
              support for their programs was undermined by reports of perfunctory
              inspections and garage owners selling inspection stickers without per-
              forming the inspections. Indiana had 19 state police officers assigned to
              monitor 4,500 stations. In the final years of the program, they spent
              much of their time investigating allegations of stickers being sold
              without inspections.

              As previously mentioned, some states have set very low inspection fees.
              Political considerations may make it difficult to raise fees, but such
              states run a risk of losing the credibility of their inspections. If inspec-
              tion fees are too low, garage owners may be tempted to do lax inspec-
              tions or to reject vehicles unnecessarily in hopes of getting repair orders.
              Ideally, the fee should be set high enough to cover the cost of a legiti-
              mate inspection that would enhance highway safety and also give the
              individual motorist timely advice about the condition of safety-related
              equipment on his or her vehicle.


              The experience of 11 states which initiated programs in the late 1960s
Conclusions   under threat of federal funding sanctions demonstrated the importance
          Y   of building public support for inspections. Seven of these states repealed
              their programs when the threat was lifted in 1976. State officials told us
              that NHTSA'S lack of a positive stance on the value of periodic inspection


              Page 23                                 GAO/RCED-90-176Periodic Inspection Programs
                                                                                              .
                 Chapter 3
                 NHTSA Intends to ResumeIts Support of
                 Vehicle Inspection Progranw




                 programs has made it more difficult to develop support for inspection
                 programs.

                 NHTSA   met its original legislative obligations, but it could do more to sup-
                 port inspection programs by taking a positive position, supporting
                 research, and providing information services to the states. Through such
                 efforts, NHTSA could help improve the effectiveness of existing programs
                 and encourage other states to initiate or reinstate periodic inspections.


                 We recommend that the Secretary of Transportation direct NHTSA to sup-
Recommendation   port periodic motor vehicle inspection through such actions as (1) spon-
                 soring research that would assist states considering the initiation or
                 reinstatement of inspection programs, (2) assisting inspection states so
                 that they share their experiences and adapt to changing automotive
                 technology, and (3) promoting public awareness of the need to properly
                 maintain the safety-critical components of vehicles.


                 As requested, we did not obtain official agency comments on a draft of
Agency Views     this report. However, we discussed the report’s contents with NHTSA offi-
                 cials, and they generally agreed with our findings. We incorporated their
                 clarifying comments as appropriate. They indicated that NHTSA has
                 reconsidered its position on the value of periodic motor vehicle inspec-
                 tions and that NIITSA now welcomes suggestions for activities it can
                 undertake in support of inspection programs.




                 Page 24                                 GAO/RCED-90-175Periodic Inspection Programs
Page 26   GAO/RCED-90-175Periodic Inspection Programs
Appendix I

States Requiring Periodic Vehicle Inspections ’                                                       l




                  States Currently Requiring Annual              States That;rtp;izt       Inspection
                         Safety Inspections                                       a
                State                          Started         State                   Started    Ended
                 Pennsvlvania                     1929         Colorado                   1937            1981
                 Maine                            1930         New Mexico                 1953            1977
                 Massachusetts                    1930         Georgia                    1965            1982
                 New Hampshire                    1931         Wyoming                    1967            1977
                 Virainia                         1932         Florida                    1968            1981
                 Delaware                         1933         Idaho                      1968            1976
                 Utah                             1936         Kentucky                   1968            1978
                 Vermont
                 --.-                             1936         South Dakota               1968            1979
                 New Jersev                       1938         Indiana                    1969            1980
                 District of Columbia             1939         Nebraska                   1969            1982
                Texas
                _______                           1951
                West Virainia                     1955
                 New York
                ___--_____                        1957
                 Rhode
                 --       Island                  1959                                                    --.
                 Louisana                         1961
                Mississippi                       1961                                           -_
                -Hawaii                           1961
                 North Carolina                   1966
                 South Carolina                   1968
                Arkansas                          1969
                 Missouri
                _-.~                              1969
                Oklahoma                          1969




                Page 26                                  GAO/RCED-90-175Periodic Inspection Programs
&pen&   II

Phncipd Studies Discussedin NHTSA’s Report


              The following eight studies compared the condition of safety-related
              components on vehicles subject to periodic motor vehicle inspections
              with those in non-inspection jurisdictions:

              1. McCutcheon, Robert W. The Influence of Periodic Motor Vehicle
              Inspection on Mechanical Condition. Ann Arbor: Highway Safety
              Research Institute, July 1968.

              This study compared vehicle condition in the metropolitan areas of
              Washington, D.C.; Cincinnati, Ohio; and Memphis, Tennessee, which
              required inspections, to non-inspection Ann Arbor, Michigan. It showed
              that inspection leads to better maintained vehicles and that the condi-
              tion of the vehicles improves with the frequency of inspection.

              2. Fisher, Franklin G., Jr., Randolph Eidemiller, and Peter Biche.
              Vehicle-in-Use Safety Standards Study: Summary and Final Report (also
              12 other ~01s.). NIITSA Reports DOT HS-800 559, 560. Newport Beach,
              Calif.: Ultrasystems, Aug. 1971.

              By comparing various inspection and non-inspection areas, this study
              found that inspection states had fewer vehicle component defects. The
              areas included were six diagnostic centers in California, one in Penn-
              sylvania, one in NewJersey, and two city inspection stations in Wash-
              ington, D.C.

              3. Fisher, Franklin G., Jr., Peter Biche, and Randolph Eidemiller. Status
              of Vehicle-in-Use Study: Summary Final Report and Final Contract
              Report. NIITSA Reports DOT HS-800 894,898. Newport Beach, Calif.:
              IJltrasystems, July 1973.

              The non-inspection states in this study, Alabama, Connecticut, Illinois,
              Maryland, and Washington, had higher defective vehicle component
              rates than the inspection states in the previous study. However, Mis-
              souri had higher defective component rates despite its inspection
              program.

              4. Hatch, William, James De Armon, and Cheryl Louie. State Inspection
              Program Evaluation and Data Analysis: Vol. I, Summary Report; Vol. II,
              Technical Report. NHTSA Reports DOT HS-802 149, 150. Silver Spring, Md.:
              Automated Sciences Group, Inc., Dec. 1976.

              By comparing selected inspection and non-inspection states using
              NIITSA'S mobile inspection van, this study found that 16 components



              Page 27                             GAO/RCED-90-176Periodic Inspection Programs
Appendix II
Principal Studies Discussedln
NH’ISA’s Report




were defective less often in inspection states and 6 were defective less
often in non-inspection states. The mobile inspection van sampled five
cities in each of the following six states: California, Illinois, Maryland,
Missouri, Pennsylvania, and Texas.

5. Innes, Joseph J. and Leslie E. Eder. Motor Vehicle Diagnostic Inspec-
tion Demonstration Program-Summary Report. NHTSA Report nor HS-802
760. Washington: Department of Transportation, Oct. 1977.

By comparing the inspection and non-inspection states of Alabama, Ari-
zona, the District of Columbia, and Puerto Rico, this study found vehicle
condition in inspection states to be better than in non-inspection states.

6. Eder, Leslie E., Noel Bleich, and Mario Damiata. The NIITSA Trial Sub-
stitute Motor Vehicle Inspection Programs. NIITSA Technical Report DCR
I-IS-803 535. Washington: NHTSA, July 1978.

The authors found that Cincinnati, which required inspections, had
fewer vehicles with defects than did the rest of Ohio. Memphis and
Chattanooga, with inspection programs, had fewer defective vehicles
than non-inspection Knoxville.

7. Final Report on Motor Vehicle Inspection Experiment. California
IIighway Patrol. Sacramento: Dec. 1974.

This study is a comparison of vehicle defects in areas with different
levels of random inspection in the state of California. It found that vehi-
cles in counties with more frequent random inspections tended to be in
better condition.

8. Eder, Leslie F:. Impact of Discontinuing Idaho’s Periodic Motor Vehicle
Inspection Program (A Before and After Outage Rate Study). NIWSA
Technical Report DOT IIS-       535. Washington: NIITSA, July 1978.

By comparing vehicle condition before and after Idaho repealed its
inspection law in 1976, this study found that repeal had a somewhat
negative effect on vehicle condition.

The following is the Indiana study of accident causation and the role of
vehicle component failures in accidents:




Page28                               GAO/RCED-90-175Periodic Inspection Programs
Appendix II
Principal Studies Mscussed in
NIiTSA’s Report




1. Treat, John R. and Ricky L. Stansifer. “Vehicle Problems as Accident
Causes-An Overview of Available Information,” SAE Paper 770117.
Warrendale, Pa.: Society of Automotive Engineers, Mar. 1977.

In this study, in-depth follow-up accident investigations were conducted
by multidisciplinary teams in Monroe County, Indiana. It concluded that
vehicle defects were definitely causal or severity-increasing in 4.5 per-
cent, probably causal or severity-increasing in a further 8.1 percent, and
possibly causal or severity-increasing in a further 12.6 percent of the
420 crashes studied.

The following three studies compared the rate of vehicle defects cited in
accident reports:

1. Costs and Benefits of Motor Vehicle Inspection. NHTSA, Office of State
Vehicle Programs. NHTSA Technical Note DOT HS-801-614. Washington:
NHTSA, Jan. 1975.

This analysis showed a decline in crashes involving defective vehicles in
Nebraska and Texas after inspection laws were enacted in those states,

2. Eder, Leslie E., Noel Bleich, and Mario Damiata. The NHTSA Trial Sub-
stitute Motor Vehicle Inspection Programs. NHTSA Technical Report HS-
803-535. Washington: NHTSA, July 1978.

By comparing crashes caused by vehicle defects in Cincinnati, which
required semiannual inspections, to Ohio as a whole, which had a
random inspection program, this study showed that fewer crash-
involved vehicles had defects in Cincinnati.

3. O’Day, James and William L. Carlson. “Detection of Defects in Acci-
dents,” SAE Paper 730584. Warrendale, Pa.: Society of Automotive
Engineers, 1973.

By comparing vehicle defect-related crashes on the Ohio Turnpike,
Pennsylvania Turnpike, Indiana Turnpike, and in the state of Texas,
this study found that the areas with a periodic inspection program had
fewer crash-involved vehicles with defects.

The following two NHTSA data analyses compared accident reports from
inspection and non-inspection states:




Page 29                             GAO/RCED-90-176Periodic Inspection Programs
                                                                         ,
Appendix II
Principal Studies Discussedin
NHT?SA'sReport




1. “Analysis Using CARDfile,” Study of the Effectiveness of State Motor
Vehicle Inspection Programs. Washington: NHTSA, Aug. 1989, p. 45.

By comparing accident reports from two inspection states (Pennsylvania
and Texas) and two non-inspection states (Maryland and Washington),
the authors found that the non-inspection states reported a significantly
higher percentage of defects on crash-involved vehicles, The difference
between the states was largest for older vehicles.

2. “Further Analysis Using FARs Data,” Study of the Effectiveness of
State Motor Vehicle Inspection Programs. Washington: NHTSA, Aug. 1989,
p. 49.

By comparing fatal accident reports from all inspection and non-inspec-
tion states, the authors found that vehicles involved in fatal accidents
had more defects in non-inspection states than in inspection states.

The following six prior studies compared fatal accident rates between
states with and without inspection programs:

1. Mayer, Albert J., and Thomas F. Hoult. Motor Vehicle Inspection: A
Report on Current Information, Measurement, and Research. Detroit:
Wayne State University, Institute for Regional and Urban Studies, Jan.
1963.

In this comparison of death rates per mile traveled during the period
1948-59, the authors reported that states with state-operated inspection
programs had lower death rates than did states with other inspection
systems, which in turn had lower death rates than states with no inspec-
tion systems.

2. Buxbaum, Robert C. and Theodore Colton. “Relationship of Motor
Vehicle Inspection to Accident Mortalitv.” American Journal of Public
Health 197-(l). July 1966, pp. 101-107.”

In this analysis of 1960 traffic death rates among men aged 45-54, the
authors reported results favorable to periodic inspection programs.

3. Little, Joseph W. The Fallacy of Evaluating Periodic Motor Vehicle
Inspection by Death Rates. Ann Arbor: Highway Safety Research Insti-
tute, 1968.




Page 30                             GAO/RCED-90-176Periodic Inspection Programs
.
    Appendix II
    Principal Studies Diecussedin
    NliTSA’e Report




    By comparing death rates in six states that introduced periodic inspec-
    tion after WWII, six states that already had inspection programs, and
    six states that never had programs, the author found inspections to
    have no effect on death rates. He also concluded that fatal crash rates
    are not a good measure for evaluating the effectiveness of inspection
    programs.

    4. Wart, Larry F. “Periodic Motor Vehicle Inspection: Its Accident Pre-
    vention Potential, Costs, and Benefits.” Springfield: Illinois Department
    of Transportation, Apr. 1976.

    By analyzing death rate trends in inspection and non-inspection states
    from 1949 to 1973, the author found that the trend had changed in 1968
    to favor the non-inspection states for the last 5 years of his series.

    6. Motor Vehicle Inspection. Harrisburg, Pa.: Pennsylvania Office of
    Budget and Administration, Jan. 1981.

    This is a regression analysis of state injury and crash data. The authors
    did not find significant differences between inspection and non-inspec-
    tion states when controlling for other important factors.

    6. An Assessment of Pennsylvania’s Periodic Motor Vehicle Inspection
    System. Pittsburgh: Carnegie-Mellon University, Program in Engineering
    and Public Affairs, Dec. 1975.

    This study found that random-inspection states had the lowest fatality
    rates in relation to miles traveled, followed by states with semiannual
    inspection, states with annual inspection, and states with no inspection
    program.

    The following two studies compared accident rates within single states:

    1. Schroer, Bernard J. and William F. Peyton. The Effects of Automobile
    Inspections on Accident Rates. Huntsville, Ala.: University of Alabama,
    Aug. 1977.

    This comparison of crash rates of inspected and non-inspected vehicles
    in Huntsville, Alabama, found that inspected vehicles had a lower crash
    rate, estimated at between 9 and 21 percent.




    Page 31                             GAO/RCED-SO-176
                                                      Periodic Inspection Programs
Appendix II
Principal Studies Discussedin
NHlSA’s Report




2. Jackson, Barry, Peter D. Loeb, and Karen A. Franck. Comprehensive
Analysis of the New Jersey Motor Vehicle Inspection System. Newark:
New Jersey Institute of Technology, Aug. 1982.

This is a regression analysis that uses data from 1929 to 1979 in the
state of New Jersey. The authors concluded that the existence of an
inspection program saved an average of 304 lives and avoided 37,910
crashes per year.

The following three data analyses compared accident statistics among
states:

1. “Comparison of Fatal Crash Rates Across Model Years in a One-Year
Crash Period,” Study of the Effectiveness of State Motor Vehicle Inspec-
tion Programs. Washington: NHTSA, Aug. 1989, p. 39.

By using fatal accident crash data from 49 states, the authors concluded
there is no clear indication that crash involvement rates across vehicle
model years are consistently different in non-inspection states and
inspection states.

2. “Comparison of Fatal Crash Rates Across Crash Years,” Study of the
Effectiveness of State Motor Vehicle Inspection Programs, Washington:
NHTSA, Aug. 1989, p. 41.

Comparing fatal accident rates of 1975 vehicles from 1975 to 1986, the
authors found no trends favoring inspection states as the vehicles got
older.

3. “Analysis of Total Crash Involvement Rates,” Study of the Effective-
ness of State Motor Vehicle Inspection Programs. Washington: NHTSA,
Aug. 1989, p. 43.

NHTSA  found that 4 inspection states had a 17-percent lower total acci-
dent rate than 6 non-inspection states. After adjusting the data, NHTSA
concluded that there was no evidence in the data examined to suggest
that periodic motor vehicle inspection programs affect the crash
involvement rates of older vehicles compared with newer vehicles.




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                                                  Periodic Inspection Programs
           F

Appendix III
    L
Major Contributors to This Report


                        Ron E. Wood, Assistant Director
Resources,              Cheryl A. Donahue, Staff Evaluator
Community, and
Economic
Development Division,
Washington, D.C.
                        Donald J. Heller, Issue Area Manager
Cincinnati Regional     Kenneth R. Libbey, Evaluator-in-Charge
Office                  Matthew Byer, Staff Evaluator




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