Police sometimes rely too much on eyewitness identification while investigating crimes, and that can lead to the wrong person being arrested, says the International Association of Chiefs of Police.
The police chiefs’ group released a report today that recommends ways to reduce wrongful arrests and convictions. Eyewitness testimony can be unreliable, and prosecutions based exclusively on a single witness’s identification without any corroborating evidence “is inherently weak,” the report says.
“Wrongful identification clearly can serve as the first step along a continuum of actions leading to wrongful arrest, prosecution and conviction,” the police chiefs’ report says. “Even after an identification is made, the investigation should continue to make sure that the actual offender has been identified.”
There are 1,250 cases since 1989 in which a person was convicted of a crime and later cleared of the charges or pardoned because of new evidence of innocence, according to the National Registry of Exonerations, a joint project of the University of Michigan and Northwestern University law schools.
The police chiefs’ report is based on an August 2012 meeting of 75 law-enforcement and criminal justice experts co-sponsored by the Justice Department’s Office of Justice Programs. The study recommended using a “double-blind” method of eyewitness identifications of suspects, in which neither the witness nor the police officer conducting the procedure knows the identity of the primary suspect. Witnesses should be shown photos or individuals one at a time instead of as a group, it said.
It also recommended making audio or video recordings of all interviews involving major crimes and improving DNA testing procedures. Law-enforcement officials and prosecutors should work together to identify the major errors that lead to wrongful arrests and convictions, the report says.