The relationship between driver aggression, violence, and vengeance.

A distinction is made between mild driver aggression and driver violence as unique constructs that differ mainly in frequency of occurrence and severity of outcome. Drivers completed questionnaires assessing the likelihood of engaging in mild driver aggression, the frequency of past driver violence, driving vengeance, and willful violations. Violence was predicted by the interaction of mild aggression and vengeance, such that violence was greater among aggressive drivers, but only for those with elevated levels of vengeance. Driver violence was also predicted by the interaction of mild aggression and violations. Specifically, violence was greater among aggressive drivers reporting traffic violations. The present findings suggest that mild driver aggression and driver violence are linked within a small group of drivers that hold other dangerous driving attitudes and behaviors as part of their typical driving repertoire.