False Evidence, DNA, and Innocence

Rufus notes the rumor that the West Memphis Three are about to be (or, it seems, have been) freed. Several problems with the Wikipedia article, but:

The West Memphis Three are three men who were tried and convicted of the murders of three boys in West Memphis, Arkansas on May 5, 1993. During the trial, the prosecution put forth the idea that the only purported motive in the case was that the slayings were part of a Satanic ritual.

Damien Echols was sentenced to death, Jessie Misskelley, Jr. was sentenced to life imprisonment plus two 20-year sentences, and Jason Baldwin was sentenced to life imprisonment.

In July 2007, new forensic evidence was presented in the case, including evidence that none of the DNA collected at the crime scene matched the defendants, but did match Terry Hobbs, the stepfather of one of the victims, as well as a friend of Hobbs’ whom he had been with on the day of the murders.

One of the defendants, Damien Echols, was deemed to have “… serious mental illness characterized by grandiose and persecutory delusions, auditory and visual hallucinations, disordered thought processes, substantial lack of insight, and chronic, incapacitating mood swings.” Stands to reason, of course, that prosecutors would ask him to speculate on how the boys might have been killed… and that these speculations would be used against him. It appears that only the introduction of DNA evidence many years later helped set him free. How many others never got that chance? We may never know.

Yes, yes, “anything you say can and will be used…” et cetera et cetera. We’ve heard it all before.

But you don’t get fair warning — almost no one does — that interrogators in our justice system are allowed to lie to you during the course of the interrogation, and indeed can say almost anything to get you to confess. “We found your fingerprints on the murder weapon” is a perfectly valid form of interrogation, or so the courts have held. One study found that 92% of investigators had used false claims to get a confession.

It should be no wonder, then, that so many innocent people sign confessions. They may be counting on the justice system to sort things out later, or counting on the goodwill of the jury, or just trying to end a highly unpleasant experience in whatever way they can. No one should have to face a choice like that. From the Economist:

Saul Kassin and Jennifer Perillo of the John Jay College of Criminal Justice in New York used a group of 71 university students who were told they were taking part in a test of their reaction times. Participants were asked to press keys on a keyboard as they were read aloud by another person, who was secretly in cahoots with the experimenter. The volunteers were informed that the ALT key was faulty, and that if it was pressed the computer would crash and all the experimental data would be lost. The experimenter watched the proceedings from across the table.

In fact, the computer was set up to crash regardless, about a minute into the test. When this happened the experimenter asked each participant if he had pressed the illicit key, acted as if he was upset when it was “discovered” that the data had disappeared, and requested that the participant sign a confession. Only one person actually did hit the ALT key by mistake, but a quarter of the innocent participants were so disarmed by the shock of the accusation that they confessed to something they had not done.

Robert Horselenberg and his colleagues at Maastricht University, in the Netherlands, have come up with similar results. In an as-yet-unpublished study, members of Dr Horselenberg’s group told 83 people that they were taking part in a taste test for a supermarket chain. The top taster would win a prize such as an iPad or a set of DVDs. The volunteers were asked to try ten cans of fizzy drink and guess which was which. The labels were obscured by socks pulled up to the rim of each can, so to cheat a volunteer had only to lower the sock.

During the test, which was filmed by a hidden camera, ten participants actually did cheat. Bafflingly, though, another eight falsely confessed when accused by the experimenter, despite participants having been told cheats would be fined €50 ($72).

The number of innocent confessors jumps when various interrogation techniques are added to the mix. Several experiments, for example, have focused on the use of false evidence, as when police pretend they have proof of a person’s guilt in order to encourage him to confess. This is usually permitted in the United States, though banned in Britain.

False evidence causes false confessions. False confessions mean that criminals go free.

But hey, using false evidence is just being tough on crime, right?