Wed November 13, 2013
Dr. Max Guyll, Iowa State University – Psychology of False Confessions
In today’s Academic Minute, Dr. Max Guyll of Iowa State University reveals how an innocent person can be driven to confess to a crime.
Max Guyll is an assistant professor of psychology at Iowa State University in Ames, Iowa. His research addresses topics related to health psychology, with a specific focus on issues relating to stress, physiologic reactivity, ethnicity, personality, and interpersonal influences. He earned his Ph.D. at Rutgers University.
Dr. Max Guyll – Psychology of False Confessions
Imagine you’re arrested for murder, but you’re actually innocent. You’re read your rights and told, “Anything you say can and will be used against you in a court of law.” Then you’re asked if you’re willing to speak with the police. Because you’re innocent, you have nothing to hide. So you waive your rights, and start talking.
Though you probably don’t believe it, this decision could start a chain of events that ends up with you falsely confessing to the murder, even though you’re completely innocent. Among convicted prisoners, who were later proven innocent by DNA testing, one in six had falsely confessed to the crime during police interrogation. People underestimate the power of police interrogation to make them falsely confess.
My colleague Stephanie Madon and I sought to understand why the innocent might be so willing to cooperate. In our research we created a situation in which some people were led to commit a minor academic offense, but others were not. So some people were guilty and some were innocent. Afterwards we accused everybody, both the guilty and the innocent people, and simultaneously measured their blood pressure to assess their stress.
The blood pressure of the innocent people rose less than the blood pressure of the guilty people, indicating that the innocent people felt less stress and were less afraid when accused. And the less fear you feel, the less likely you will be to take self protective actions, like invoking your right to silence, or getting a lawyer.
And in the end, even though they did not do it, 43 percent of the innocent people in our study falsely confessed to having committed the offense. And in our study, we only interrogated people for a few minutes, but real police interrogations can go on for hours and hours. Innocent people may come to believe that the only way to escape the interrogation is to give up and confess. It can be like arguing with someone for hours on end; you reach a point where you’re willing to say anything just to make it stop.