Accident reconstruction is a very complex subject, and there are various softwares (CRASH5, etc.), but these softwares are costly. Therefore, I would be glad if you could suggest a software that can provide a free and visual solution.
Pycrash is a free, open-source Python-based software package that, in its current state, can perform basic accident reconstruction calculations, automate data analyses, simulate single vehicle motion and, perform impulse-momentum based analyses of vehicle collisions.
Key aspects of reconstructing an accident may include:
Thorough inspection of the vehicle or vehicles involved in the accident.
Analysis of vehicle and crash site images.
Review of the traffic collision report, deposition transcripts, witness statements, crash test reports, published studies, and other documents.