Causes and consequences
Aggressive traffic behaviour means that a road user behaves in such a way that he/she deliberately causes damage to another road user or threatens to do so. We distinguish two types of aggression: angry aggression and instrumental aggression.
Angry aggression: seeking revenge
Someone who feels that he/she was deliberately harmed by someone else, seeks retaliation or satisfaction. This is characteristic of angry aggression. The emotion at the root of this type of aggression is anger (see Emotions in traffic). Seeking revenge can take all sorts of forms: insulting by obscene gestures, swearing, hitting the car, overtaking quickly again, tailgating, and cutting in. In serious case, somebody is threatened by dangerous manoeuvres or forced to stop, possibly resulting in casualties.
Instrumental aggression: own interest first and foremost
Instrumental aggression is not the result of anger and seeking revenge. It is an aggression type that mainly serves one's own interest and, therefore, does not consider anybody else's interests. It is expressed in a much more varied way than angry aggression. Driving fast to get somewhere quickly or just because one enjoys it can be seen as examples of instrumental aggression. Little is known about its causes. Every type of damaging or excessive behaviour can be instrumental aggression; it depends on whether it was deliberate or not. What is more, unintended damaging or excessive behaviour can be taken by someone else as being deliberate, and therefore as aggressive.