5. Driver Training and Teenage Drivers
Although DMV has no direct program authority for driver training, CVC Section 1657 authorizes the department to advise the Department of Education (DOE) and other cognizant organizations on driver education standards. CVC Section 1659 also authorizes the department to develop standards and educational programs for disqualified (suspended or revoked) drivers. With respect to novices, present California law requires that a driver must be at least 18 years old to qualify for a license, unless he or she has passed a prescribed course in behind-the-wheel training. The department has conducted and published several studies pertaining to the effectiveness of novice-driver training.
- Driver training effectiveness. In 1965, R&D performed a statistical evaluation (Research Report No. 21) of the driving records of thousands of teenage drivers. This study found no evidence that driver training was associated with reduced accidents. Further, it found no evidence to support raising the licensing age to 18 for applicants who had not completed driver training. To our knowledge, this was the first empirical effectiveness study questioning the alleged value of driver training. Despite the findings and recommendations of the study, the legislature passed a 1967 law (still in force) requiring persons to complete an approved driver training course in order to be licensed prior to 18. This study is obviously not an example of successful policy influence but it is cited for historical context and consistency with later studies showing behind-the-wheel training to be of little or no value in decreasing the accident rate of young drivers.
In 1971, R&D published a much more in-depth analysis (Research Report No. 38) of factors which differentiate accident-involved teenagers from those not involved in accidents during their first 4 years of driving. This study found that accident-involved drivers had lower grade point averages (GPA), poorer citizenship grades, lower socio-economic status (SES), and greater access to a car before and after licensing; they were also less likely to have completed a behind-the-wheel driver training class. However, the finding that driver training was associated with reduced accidents was not proof of a cause-effect relationship because the study also showed that students with driver training (which had been voluntary for these subjects) had "more favorable" characteristics than untrained students. For example, the trained group had substantially better school scholarship records (GPA) and citizenship grades--factors that are predictive of safe driving. When these background biases were controlled statistically, all subsequent driver record differences between trained and untrained males disappeared. The same "evaporation" also occurred for females except on one variable: trained females had significantly fewer fatal and injury accidents than did untrained females. The results of the above study were instrumental in causing some insurance companies to base insurance discounts on school performance instead of driver training status.
Two subsequent studies by the Insurance Institute for Highway Safety (IIHS) suggest that the existence of driver training in the schools actually increases accidents by encouraging some teenagers to drive at an earlier age. A large-scale experimental study funded by NHTSA in Dekalb County, Georgia also failed to demonstrate any net accident reduction attributable to driver training. In a recent presentation (1996) to the Transportation Research Board, DMV's Research Chief summarized the results and implications of the Dekalb driver training study and of the various reanalyses of the original data. This paper stresses the importance of the choice of the appropriate unit of analyses in assessing the policy implications of the Dekalb study. The evidence showing an accident increase due to training occurred because driver training led to a larger proportion of the eligible teen population obtaining a driver's license and a tendency to obtain the license at an earlier age. Hence, driver training led to increased driving exposure-which, in turn, led to more accidents in the applicant pool assigned to training. When the analyses were confined to differences in the accident rates of those applicants in the control and trained group who were licensed, there was suggestive evidence of a small short-term (6 months) accident reduction attributable to training. It was concluded that the challenge facing driver educators and driver license administrators is to integrate driver training and driver licensing in a way that avoids premature licensure and increased exposure. A variety of approaches based on graduated licensing models have been proposed for accomplishing this objective.
In 1989-90, the administration discontinued allowing schools to utilize the state's Penalty Assessment Fund to subsidize behind-the-wheel training. This policy decision, combined with the above evidence, has resulted in most California school districts deleting behind-the-wheel driver training from their curricula. As a result, there has been some reduction in the licensure rate of those under 18. This reduction has caused some authorities to become concerned over the possibility of increased unlicensed driving and is evidence of reduced access to driver training among segments of the population who cannot afford to pay a commercial provider. Since formal driver training has also been shown to produce better performance on DMV road tests, there is also some risk of an eventual decline in the competency level of the California driving population if growing proportions of novice drivers delay licensure to age 18 and receive no formal training. Whether or not such a trend will eventually have a detrimental effect on traffic safety cannot be determined with certainty from the present evidence. However, an unpublished analysis by R&D in 1995 showed no evidence of a detrimental effect on safety as of that date.
- Private-school driver training. In 1969, legislation was passed requiring DMV to perform a scientifically valid study on the efficacy of commercial (private) vs. public (high school) driver training. To assure objectivity, the study was subcontracted to the UCLA Institute of Transportation and Traffic Engineering under the direction of R&D. The results showed that commercially-trained and publicly-trained students had equivalent post-training accident frequencies. Since commercial training was cheaper, the report concluded that it was a more cost-effective method of training. The report also found that variations in length of training (3, 6, and 10 hours) did not result in differences in post-training accident rates. This was true for both commercial and public programs. This latter finding was subsequently used by the Department of Education in defense of its "competency-based" approach to driver training, in which some students receive less than the standard 6 hours.
- Experimental driver training and teenage licensing studies. R&D has conducted several studies assessing innovative approaches to driver training and the licensing of teenage drivers. One study (Research Report No. 35) evaluated whether driver training graduates who were considered by their instructors to be in the upper 10% of their class should have their drive test waived by DMV. R&D determined that these "best" students, although receiving higher than average scores and pass rates, still had a failure rate of 15% on the DMV drive test. This was considered too high for DMV to recommend establishment of a test-waiver program.
A second study (Research Report No. 58) evaluated a driver training program in which some on-the-road training was replaced by extensive training on a driving range. R&D performed an experimental (randomized-assignment) evaluation of the program under contract with a local public school district. The range program proved to be more effective than the standard program in reducing subsequent accident rates and, to our knowledge, is the only rigorous empirical demonstration in the literature of a positive net accident effect due to any driver training variable. By showing that one form of training is more efficacious than another, it also demonstrated that training in some form has value.
A third study, done in several stages by DDSL and R&D during the period 1980-1985 (Report No. 99), led to implementation of the current provisional licensing program. The recommended program proposed to achieve accident reduction in five ways: (1) increased parental involvement in the training process, (2) a more rigorous screening/testing process, (3) a post-licensing control system whereby intervention begins upon the first conviction or accident, (4) imposition of a midnight to 5 am driving curfew, and (5) a requirement that the licensee wear seat belts. The final version of the program, as authorized by the Legislature, contained only the first three of the above elements. The seatbelt requirement became moot when the Legislature subsequently enacted a law requiring that all drivers and passengers wear seat belts. The curfew component was rejected by the Legislature.
The final report to the Legislature on the provisional license program (Research Report No. 116) led to its being permanently adopted by California for all applicants under the age of 18. The report documented a statistically significant reduction (5.3%) in teenage accident frequency attributable to the provisional license program.