Christmas 1981 was anything but merry for Danny Brown. He was 25 then and spending time with Bobbie Russell, a 28-year-old woman he had recently met.
Before the holidays were over, Brown would be in prison, accused of raping Russell and strangling her with a string of electric lights from a Christmas tree. Soon after, he was sentenced to life.
Brown passionately defended his innocence, and in January 2001, his supporters leapt on advances in DNA testing to prove that a semen sample from Russell that had been kept refrigerated at a crime lab in Toledo, Ohio, was not Brown's. But that wasn't enough to get Brown released. Russell's 6-year-old son, the only witness to the crime, initially said that two people attacked his mother. If he was telling the truth, Brown conceivably could have been an accomplice.
So Brown took and passed a polygraph test. And in April 2001, based on both the DNA and lie detector results, an Ohio judge freed Brown, who had by then spent half his life in prison for a crime he didn't commit. "The polygraph helped liberate Brown from a 19-year-long nightmare," says Jim McCloskey, the founder of Centurion Ministries in Princeton, New Jersey, an organization that helps to free falsely convicted people and was instrumental in Brown's release.
The ability to distinguish truth from lie, to tell the guilty from the innocent, is one of the most basic challenges in all human interactions. Everyone lies, and everyone tries to spot a liar. No one is consistently successful at either. Hence the strong appeal of a scientific device that could unequivocally separate fact from fiction; today, the attempt to perfect such a device is spurring investigators to delve into the complexities of biology and human nature.
Until now, the modern polygraph, a 66-year-old invention, has been the only broadly accepted technology for exposing liars. More than 2,000 private examiners around the country routinely administer polygraph tests to determine facts in cases ranging from marital infidelity to employee theft. In numerous well-publicized instances, polygraphs have uncovered deeply buried lies. Susan Smith, who drowned her two young sons in 1995 in a car she let roll into a South Carolina pond, confessed after failing three polygraph exams, though the authorities had no other evidence linking her to the murders.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.