How a False Confession Can Sway a Jury

Feb. 4, 2009— -- In 1977 an Illinois court found Michael Evans guilty of unspeakable crimes, including murder, kidnapping, rape, deviant sexual assault and indecent liberties with a child. He was sentenced to 400 years in prison.

The conviction was based largely on a lone eyewitness identification of Evans as the perpetrator. But DNA testing subsequently proved that Evans wasn't the culprit. He was released in 2003 after serving 26 years in prison for a crime he didn't commit.

The witness later told investigators she wasn't all that certain of her identification, but was reassured when she was told there was a confession. That's according to a remarkable organization called the Innocence Project, which has used DNA evidence to help clear 232 people who were erroneously convicted of crimes they never committed.

Are these troubling cases rare? They may be only the tip of the iceberg, because DNA evidence that has proved so conclusive in cases pursued by the Innocence Project is rarely available. And false confessions, it turns out, aren't all that rare, either. They figure in at least 25 percent of the cases that have been cleared by evidence collected by the project.

Now, new research shows that a confession, even if false, can have an "astonishing" effect on witnesses who were quite sure they had picked the right criminal in a lineup. The research is part of two experiments conducted at several universities showing that false confessions can contaminate an entire court proceeding, and witnesses who are interrogated immediately after seeing a crime become more -- not less -- susceptible to later misinformation.

The research adds to a growing body of scientific literature revealing that we often don't see what we think we've seen, and even credible witnesses are vulnerabile to false testimony and harsh interrogations. It is particularly timely with the approaching trials of suspected terrorists now housed in Guantanamo Bay, Cuba, because there will likely be many confessions in connection with those cases, and some of them will almost certainly be false.