PORTLAND, Ore. — The American legal system offers few moments as dramatic as an eyewitness to a crime pointing his finger across a crowded courtroom at a defendant.
The problem is that decades of studies show eyewitness testimony is right only about half the time — a reality that has prompted a small vanguard of police chiefs, courts and lawmakers to toughen laws governing the handling of eyewitnesses and their accounts of crimes.
Reform advocates say procedures long regarded as solid police work, from bringing a witness to a crime scene where he might see a suspect in handcuffs to the subtle encouragement of a detective during a police lineup, can fundamentally alter what someone believes they saw.
"It's not the case that eyewitnesses are inherently unreliable," said Gary Wells of Iowa State University, who has researched the field of eyewitness identification since the 1970s. "But we can make it better by cleaning up the procedures around it."
Prosecutors, however, have opposed the efforts, arguing the changes erode their powers, even as studies show that witnesses are about half as likely to choose the correct suspect out of a lineup as they are to choose some combination of the innocent fillers or no suspect at all when the correct one is present.
The reexamination of eyewitness testimony comes at a time when technology and other forensic analysis are being given greater weight.
"What we see is a fairly organized and aggressive attack on all forms of evidence prosecutors use to get convictions," said Scott Burns, executive director of the National District Attorneys Association.
Burns said criminal defense attorneys, groups that try to get wrongful convictions overturned and the American Civil Liberties Union are part of a bloc that is selecting outlier cases of prosecutorial misconduct or witness mishandling and applying that to the entire system.