User:Meadair/Police lineup

Potential contributors to inaccuracy
Errors due to familiarity

Simple exposure to a certain face contributes to the illusion that an innocent person was the guilty suspect. For example, a witness might identify a receptionist as the guilty suspect simply because he or she had previously seen the receptionist's face, misattributing the familiarity to seeing the individual committing the crime instead of in his or her position as a receptionist. This concept is also connected with source-monitoring errors, in that the source of the familiarity is misattributed and unconsciously transferred to an innocent bystander. See also Familiarity heuristic.

Own-group recognition bias

Witnesses are more likely to correctly identify the faces of those with whom they share common features, such as race, age, and gender. See also Cross-race effect, In-group favoritism, Sex differences in eyewitness memory.

Framing bias

Subtle framing characteristics influence a witness' response to a question. For example, if a police officer asks which of the individuals in the lineup committed the crime, the question implies that one of the individuals is guilty, increasing the likelihood that the witness will pick someone from the lineup without positive recognition.

Additionally, the overwhelming majority of witnesses will identify a suspect from a lineup even if the actual perpetrator is not included in the lineup, often depending on how the instructions for choosing a suspect were presented. See also Framing effect (psychology).

Post-identification feedback effect

Delivering either confirming or dis-confirming feedback to witnesses identifying a suspect has been shown to distort their reported perception of the suspect in question. Providing feedback to a witness after identifying a suspect changes the way they remember the quality and clarity of the memory, the speed and certainty of their identification, and other factors, even when witnesses believed the feedback had not influenced their report. During questioning or viewing pictures in a lineup, it was found that an eyewitness made a tentative judgement that a certain picture might be the guilty suspect, to which an officer administering a lineup answered, "okay." However, upon returning to that picture months later at trial, the witness expressed no doubt that the previously hypothesized picture represented the guilty suspect.