Distance and orientation in suspect identification under poor illumination conditions: Simulation of a real case.

Visual perception plays a crucial role within witness psychology. It is not unusual that the accused are found guilty only on the basis of eyewitness identification. The Italian national TV asked us to reproduce the visual conditions under which a witness was in at a mafia murder, and to run an experiment to test whether in these conditions she could have unambiguously identified the killer. A group of 72 observers has been tested. Two variables were manipulated: distance (killer-observer: 6 or 16 meters) and orientation (killer viewed frontally, 45 degrees left, 45 degrees right). Illumination conditions were controlled (low intensity illumination). The experiment was run in 2 different days. In the fist day, each observer (12 for each condition) viewed the killer for 1.5 seconds. Four days later they were asked to identify the killer among 5 look-alike persons in a simultaneous line-up. Results show that in our stimulation conditions (low intensity illumination) both correct and incorrect identifications were not statistically different from chance, independently from both viewing distance and orientation.