An expert witness for a car accident is someone who has extensive knowledge in a particular area and can offer information in a car accident court case for either the defense or the prosecution. In most personal injury claims expert witnesses will be called to help prove a claim. In some states the law will require the plaintiff to have a expert witness to testify that their injuries are permanent in order to win damages for pain and suffering.

Car accident witnesses may be able to testify about the following: accident reconstruction, vehicle products liability, fuel system integrity, interior flammability, electrical engineering, crash data retrieval analysis, and occupant restraint systems and airbags.