In 1977, police in Warminster Township, Bucks County, Pennsylvania were certain that they had nabbed the culprit in a particular case, but they lacked critical evidence connecting the suspect to the case.
So, one of the policemen brought a metal colander dish, used for rinsing veggies, to work, ran wires from it to the police copying machine, and placed a paper saying "HE'S LYING" on the copying machine glass. One of the policemen leaned on the copying machine, over the "COPY" button, as though to relax. Another brought in the suspect, sat him in a chair and placed the colander dish on his head.
They informed the nervous-but-skeptical suspect that the machine would tell them every time he was lying, and they began to question him.
Every time the defendant gave an answer which the police suspected was a lie, the policeman leaning on the machine leaned a little too hard on the "COPY" button and out would come another paper reading, "HE'S LYING."
After this went on for a few minutes, the Defendant couldn't take it anymore. He broke down, and confessed to the crime with a full, detailed confession.
Pennsylvania Judge Isaac Garb affirmed by letter to a writer that this story is absolutely true, and that he was the judge on the case.