Crime scene reconstruction. Screen display of a three-dimensional (3D) computer model being used to reconstruct a crime scene. The model shows a dead man lying on a floor with a brown line indicating the trajectory of the bullet that killed the man. There are also footprint marks on the floor. Detailed recreation of the crime scene can allow investigators to extrapolate from the known evidence and deduce what may have happened. Reconstructions can also be used when examination of the actual crime scene is not possible, for example in very old cases, or where further forensic contamination prevents access. Photographed at the Macaulay Institute, Aberdeen, UK.