Statement of purpose Motor vehicle crashes are a major cause of mortality and injury for U.S. teenagers. This risk is highest for male teenagers with multiple male teenaged passengers. This research was undertaken to examine how multiple peer passengers influence male teenagers’ driving behaviours.

Methods/approach In this experimental driving simulator study, male teenagers drove two drives, one with two of their own friends as passengers, and one alone. Driving data was collected including intersection behaviours, distraction behaviour, eye-movements, and in-vehicle interaction data. These were compared between the two passenger presence conditions.

Results We had hypothesised that drivers would engage in riskier behaviours when with passengers. However, the results showed that teenagers did not drive riskier with passengers. We had also hypothesised that drivers with passengers would be more distracted, but we found no differences in distraction behaviours. Finally, an analysis of the interactions between the driver and the passengers indicated that although some passengers encouraged risk taking, drivers were not swayed by the pressure.

Conclusions Similar to the mixed evidence in the literature, this study found no significant effects of multiple passengers on drivers’ behaviours. These results underscore the necessity of conducting larger-scale, perhaps naturalistic research to better examine these issues.

Significance and Contributions to Injury and Violence Prevention Science This study addresses issues of young driver safety by examining the influence of multiple male teen passengers on risky driving behaviour, a significant factor associated with the high fatal and non-fatal injury rates for teenagers, directly relating to injury aetiology and prevention. Understanding passenger influences on teenage drivers can provide evidence that can inform policy to help reduce the high rates of injuries in the young driver population.