Mapping complex shooting scenes is challenging, because it inevitably relies on police reports, eyewitness reports, and evidence from the shooting scene. It is therefore crucial to obtain comprehensive information from all persons with direct knowledge and vision of what happened at the shooting scene as soon as possible after the incident. Further, as soon as practical, reconstructionists should visit the shooting scene in order to diagram it. This involves placing all parties in the event vicinity in the proper place in the course of the event's unfolding. All evidence on bullet trajectories in relation to officer placement in the scene should be determined. Based on reports from the involved parties and physical evidence from the shooting scene, the reconstructionists must decide on the most likely scenario before engaging in 3D mapping. With a 3D model and accurate scene measurements, a 3D diagram can show where a shooter was standing, the direction he/she was firing, and the elevation of the weapon in the shooter's hand. The trajectory path can be extended to show where the bullets may have entered other structures or vehicles. With a clear and accurate 3D diagram, those who are assessing what happened, and why, can envision what the shooting officer most likely saw at the time of the shooting, what the officer was up against, cues for his/her decision to shoot, and what the suspect saw and did in interaction with the officer.