Overtaking (passing) is a high risk maneuver for road users, still drivers often accept this risk and moreover they often commit irregular overtaking maneuvers. The paper gives some overview on the background of traffic violations and irregular overtaking maneuvers. Driver's decisions before and during the irregular overtaking maneuvers are similar to the normal ones, except of the decision about committing the violation itself. A decision support application is recommended to reduce the number of overtaking violations and useless overtakings.