Road traffic accidents demand considerably more lives than criminal offences against persons, that gives already a reason for adequate actions in order to prevent traffic accidents. The basic criteria of accident prevention are knowledge of the causes of and circumstances leading to accidents. In the previous decades it was mentioned several times from several sources, that the high petrol prices had caused a significant decrease in the number of road traffic accidents. This study aims to explore by mathematical methods if there is a causal link between petrol price levels and the number of road traffic accidents.