Use of ‘truth serum’ under fancy new name is still a bad idea

The Colorado judge presiding over the trial of accused mass-killer James Holmes raised a lot of eyebrows last week when he ordered Holmes to undergo polygraph testing and a “narcoanalytic interview” if he chooses to use an insanity defense. The results of those tests apparently could be used against Holmes if he is found to be sane and goes to trial.

The problems with polygraph testing are fairly well-known, but the use of a ”truth serum” in criminal cases has been equally troubling. Forensic psychologist Karen Franklin explains why in her Psychology Today blog here.

The case of Melvin Lee Reynolds, who became a suspect in the 1978 abduction, rape and murder of a 4-year-old boy in St. Joseph, Missouri, is a good example of how the use of a ”truth serum” can lead to a wrongful conviction. Reynolds strongly insisted on his innocence. Police eventually persuaded him to agree to be questioned after being injected with sodium amytal, a frequently used ”truth serum.” They then convinced Reynolds that a verbal slip he made during the interview was an admission of guilt, and he signed a confession. Reynolds quickly recanted, but the damage was done. He was convicted and sentenced to life in prison.

Two years later, another child disappeared from the same shopping mall where Reynolds allegedly had abducted his victim, and a drifter named Charles Hatcher was charged with the child’s abduction and murder. Hatcher not only confessed to that murder but also the murder of the child Reynolds was in prison for and several others. Hatcher’s confession was far more detailed and accurate than the statement Reynolds gave, and Reynolds was released from prison the day after Hatcher pleaded guilty to the crime in 1982.

Dressing up the long-discredited use of ”truth serum” in a fancy term like “narcoanalytic interview” doesn’t change the fact that it is a highly unreliable procedure that can lead to erroneous conclusions.