In analysing the causes of the dangers posed in road traffic, which often end up in accidents or other road incidents, we focus on evidence of violated road safety rules. This is an oversimplification of the problem, since it does not allow for getting to know the determinants of indicated violations which often come down to the broadly assessed state of health of road users, their psychophysical characteristics and personality, as well as their fatigue and mental state. The author of this paper not only analyses the aforesaid problems from the legal point of view, but also tries to look at them in an interdisciplinary way. The author further demonstrates how little we know about it; hence without in-depth exploration of the subject, preceded by credible scientific research, it will be extremely difficult to take reasonable preventive measures, whilst deterring with severe sanctions simply does not work.