Critical evidence in a car accident injury case includes the police crash report, photographs of the scene and vehicle damage, witness statements, medical records documenting injuries and treatment, and any available video or surveillance capturing the collision. Timely collection of this evidence helps establish liability and the connection between the accident and injury. Medical documentation that shows diagnosis, recommended treatment, and recovery progress is especially important for quantifying damages. Other valuable materials include repair estimates, lost wage records, and documentation of ongoing impairments. Expert opinions, such as accident reconstruction or medical specialists, can be helpful in complex cases where fault or causation is contested. Preserving evidence early and coordinating with investigators strengthens your negotiating position with insurers and provides a solid foundation for litigation if needed.