Abstract: In November of 2006 a family with small children was crossing the street in downtown Denver when they were hit by a DUI driver that fled the scene. A license plate that was left behind led to the arrest of the driver and passenger a few hours after the collision. There were contrasting witness statements about what happened due to the traumatic nature of the event. Several video cameras in the area captured the event. The video recordings from those cameras were used in conjunction with a scale diagram and traffic engineering report to clarify the actual sequence of events as well as determining the vehicle’s speed. The author was involved in this investigation and discusses the methodology behind the speed determination as well as how he was able to determine the driver had a red light when the light was not visible in the video.