The effectiveness of licence restriction for drink drivers

In Queensland, license restriction is frequently used as an alternative to full disqualification for drink driving in an attempt to alleviate the potential economic hardship caused by inability to drive. However, there is a possibility that license restriction may undermine the deterrent effect of license loss and may fail to break the nexus between drinking and driving. Accordingly, it is important to examine the effectiveness of license restriction, as opposed to full disqualification, in preventing reoffence during the sanction period. We made this comparison in a cohort of over 17,000 Queensland drivers either disqualified (83%) or granted a restricted licence (17%) for a drink driving offence in 1993, 5% of whom reoffended during the sanction period. The restricted drivers were on average 5 years older than those disqualified, and fewer had a recent history of drink driving (11% v.37%). The median sanction period was similar in both groups. After controlling for age, previous drink driving history and length of initial sanction, there was little difference between the two groups. Drivers with license restriction appeared to reoffend somewhat less than disqualified drivers (by about 6%), but the difference did not approach statistical significance. While concerns about the effect on general deterrence remain, it appears that granting permission to drive on a restricted basis is no less effective as a specific deterrent than full disqualification.