Opposing party claims the opposite. What to do?

Unfallgegner behauptet das Gegenteil. Was tun?

If you have been involved in an accident, it can happen that the other party in the accident presents the incident differently than you think it happened. What should you bear in mind? Accident reconstruction is made more difficult It can sometimes be very difficult to reconstruct the course of the accident and to clarify the question of fault properly if the statements of those involved in the accident are not congruent. [...]