Passenger restrictions for young novice drivers

ACRS Policy Position

Information on young driver crashes should be re-examined to determine if there is a case on safety grounds for imposing passenger restrictions on P-plate drivers, having regard to whether doing so can be effectively carried out and enforced.

Objective

To reduce road trauma amongst young drivers and accompanying passengers.

Discussion

At a time when the road toll appears to be levelling out (as it is world wide) it may be worth reconsidering measures not so far implemented that have the potential to reduce road trauma.

When various young driver harm and exposure reduction measures were being considered as a result of the MUARC Young Driver Research Program, passenger restrictions were rejected as a policy initiative, primarily on the grounds that they were unlikely to be effective. It was further concluded that night driving restrictions should be preferred on first principles (1, 2).

The analysis conducted at the time, from which that conclusion was drawn, showed that, for Victorian data for 1990 and 1991 (2):

Drivers under 26 years had 13.2% of crash involvements while carrying two or more passengers (for drivers under 21 years, the equivalent figure was 16.2% of crash involvements)
Young drivers have a higher proportion of their crashes while carrying passengers and, as crash severity increases, the probability that young drivers will be carrying multiple passengers increases
Young drivers have more crashes between 10pm and 5am for all occupancy classifications
Young people have more crashes between 10pm and 5am as vehicle occupancy increases
For 18-20 year olds, there were two or more passengers in 28% of crashes in the period 10pm-5am (note that the absolute numbers in this case are small).

Nevertheless the report concluded that imposing passenger restrictions would not make young drivers barred from carrying passengers any safer. One possible effect of imposing passenger restrictions was exposure transfer: young people barred from travelling as passengers might instead drive their own cars and lead to an aggregate increase in crash risk. There might also be some exposure transfer to other groups, such as parents who would then have to drive their children. Concerns were also expressed about equity and viability of imposing passenger restrictions.

The report mentioned imposing passenger restrictions as a sanction for young drivers who have committed traffic offences, but that the deterrent or punitive value of such a measure is unknown.

This is the way in which passenger restrictions are applied in the only jurisdiction that imposes them. Victoria now imposes passenger restrictions when offences have been committed by a P-plate driver that result in licence suspension. In that event, the probationer is restricted to one passenger for twelve months once the licence has been reinstated (see VicRoads web site). It is understood that the passenger restriction penalty has been used only rarely if at all.

There are a few points at which one might take issue with these findings, set out briefly below.

If the aggregate crash risk resulting from exposure transfer is not increased, Drummond found that there are benefits of imposing passenger restrictions in the late night period, estimated at 45% for novice drivers carrying two or more passengers, 37% for novice drivers carrying one passenger. This is a significant benefit
It has been argued but not shown that exposure transfer would increase aggregate risk for young people. It is not necessarily so that all young persons who would be passengers would drive their own cars. In some areas the substitute might be public transport, not more cars
Where exposure transfer is to parents and other adults ferrying young persons, the risk is less than where the driver is young
Some behaviours may not occur at all if passenger restrictions are imposed, especially at night (but some others involving young people in a number of cars might)
Some journeys, especially at night when the risk is highest, might not be made if passenger restrictions are imposed.

There are also safety and equity concerns to be addressed. Imposing night curfews would affect the employment of some young people, but exemption permits could be obtained for those who have jobs affected by a curfew. It is not expected that passenger restrictions would have much impact here. Late at night public transport is less available and dangers increase, especially for young women.

Conclusion

There are two main reasons for imposing passenger restrictions. One is to reduce the road trauma impact should there be a crash – more likely in itself for inexperienced young drivers than for other road user groups. The second reason is that several passengers accompanying a driver, especially late at night, may of itself increase risk because of skylarking, peer behaviour or simple inattention.

On the figures cited above a case can be made for some passenger restrictions. On the grounds of risk, a case can probably be made for a late night ban (eg midnight-5am) on a P-plate driver carrying more than one passenger.

There are political and practical difficulties, some of which are outlined above. There are also enforcement difficulties. Exposure transfer, especially if it results in more inexperienced young drivers driving, especially at night, needs careful consideration.

Given that the downward trend in road fatalities appears to have stalled, we may be justified in considering measures that have previously not been considered warranted. A late night passenger restriction for P-plate drivers has potential.

Note: Queensland does not have compulsory display of L and P plates.

References

Drummond AE (1994) Young Driver Research Program: A Technical and Strategic Overview of Exposure Reduction measures as a Means of Reducing Young Driver Crashes FORS, Canberra, CR 130

Triggs TJ and Smith KB (1996), Young Driver Research Program: Digest of Reports and Principal Findings of the Research FORS, Canberra CR 164