Shooting incidents are dynamic and varied, as is the evidence produced during such an event. At shooting scenes, the crime scene team will identify, reconstruct and document projectile paths, called trajectories, based on impact marks including penetrating, perforating or non-penetrating points of impact. Reconstruction of a shooting incident relies on careful examination and processing of a scene for pertinent physical evidence including defects and holes caused by projectiles. Accurate reconstruction typically requires the identification and collection of associated evidence and its subsequent analysis in the Laboratory.

The examination of defects and holes caused by projectiles from firearms can provide information useful in the reconstruction of a shooting incident. Observations of impact sites can provide information about the projectile, the firearm, intermediate objects in the path of the projectile, direction of travel of the projectile, order of shots and other information. In some circumstances, the trajectory of the projectile may be determined and this can assist in determining possible positions from where a shot originated as well as locating additional items of forensic significance such as cartridge cases.