Road safety impact of Ontario street racing and stunt driving law.

Objective: The purpose of this study was to conduct a process and outcome evaluation of the deterrent impact of Ontario's street racing and stunt driving legislation which came into effect on September 30, 2007, on collision casualties defined as injuries and fatalities. It was hypothesized that because males, especially young ones, are much more likely to engage in speeding, street racing and stunt driving, the new law would have more impact in reducing speeding-related collision casualties in males when compared to females.

Methods: Interrupted time series analysis with ARIMA modelling was applied to the monthly speeding-related collision casualties in Ontario for the period of January 1, 2002 to December 31, 2010, separately for young male drivers 16-25 years of age (primary intervention group), mature male drivers 26-65 years of age (secondary intervention group), young female drivers 16-25 years of age (primary comparison group) and mature female drivers 26-65 years of age (secondary comparison group). A covariate adjustment using non-speeding casualties was included.

Results: A significant intervention effect was found for young male drivers with, on average, 58 fewer collision casualties per month, but not for mature male drivers, when non-speeding casualties were controlled for. No corresponding effect was observed in either comparison (females) group.

Conclusion: These findings indicate a reduction in speeding-related casualties among young males of 58 fewer casualties per month subsequent to the introduction of Ontario's street racing and stunt driving legislation and suggest the presence of a general deterrent effect.