After reading of yet another case (in John Grisham’s non-fiction book The Innocent Man) in which a guy is railroaded by police into a false confession after failing a lie-detector test - he spent most of his life in prison before the real killer was found - I have to ask why this piece of junk science is still used by the police and private companies.
There just is no scientific method to determine whether someone is telling the truth. Sure, a machine can detect nervousness but it can’t tell the reason for that nervousness, and who wouldn’t be nervous taking a test in a murder inquiry. The lie-detector is pure woo, ritualistic nonsense with the ‘technician’ as the high priest. He/she is the modern equivalent of the oracle at Delphi, mystically communicating with Apollo to reveal truth to mortals. It’s absolute, total bullshit.
And yet all over the country people are being judged by this idiotic process. If the courts won’t admit them, for good reason, how are the police allowed to pressure suspects with them? How is it not unconstitutional for the agents of the state to use mystic machines to guide their thinking and harass suspects with the results?
It really is time for this stupid machine to be thrown on the scrapheap.
I was under the impression that the only reason police offer lie detectors is so that they can tell you that you’ve failed in the hopes of extracting further information from you.
Sidebar: There’s an amusing story in David Simon’s non-fiction book “Homicide: A Year on the Killing Streets” in which a group of cops loaded a photocopier with sheets of paper which had the words ‘TRUTH’ and ‘LIE’ printed on them, then had suspects place their hands on the scanner. They’d ask them questions like “What’s your name?” or “How old are you?” and the photocopier would spit out the pages with ‘TRUTH’ on them. Then they’d ask “Did you shoot Bob in an alley at 2am Sunday morning?” and, when the suspect denied it, they’d press a button and the photocopier would print the ‘LIE’ page.
Apparently, it used to work more often than you’d think. They adapted the story for a scene in The Wire, which you can see www .youtube .com/watch?v=rN7pkFNEg5c (some NSFW language) if you want. If that’s the kind of regard the cops themselves have for lie detectors, the only conclusion I can draw is that cops only offer them to gain leverage over a suspect. They know as well as anyone they’re a load of crap.
Yes, I remember both scenes, really funny. And I’m sure there are a lot of cops who know full well that lie-detectors are a bunch of crap, but I’m equally sure there are also many cops who believe in their efficacy and allow the results to guide the course of their investigation. The book I referred to above was this one in which four men wrongly spent decades in prison for two separate murders. All of the men had been happy to take lie-detector tests as they knew they were innocent. The idiotic machine indicated they were lying when they said they had not killed the girls and this result threw the men, who weren’t the sharpest knives in the drawer, into such a state of confusion and panic that it was simple for the cops to get them to confess to crimes they hadn’t committed. “Lie-detectors don’t lie”, the cops told them, and the men believed it, as did the cops themselves. The men were convicted on the sole strength of these confessions and spent decades in prison (some of it on Death Row) before the real killer was found.
There are countless such cases in which lie-detectors have been instrumental in extracting false confessions. The damn machine is an offensive stain on the American investigative process and needs to be deep-sixed forthwith.
I would say this is pretty close. The police are allowed to lie about all kinds of things to suspects, including the nature of the evidence against them. And that includes telling them about evidence that doesn’t exist at all, or mischaracterizing things that prove nothing as proving something.
Yes, I get that. But when it comes to confessions there are very strict rules. Police aren’t allowed to extract confessions under any kind of duress or pressure, the confession must be entirely free and voluntary and using the result of a lie-detector test to pressure someone into a confession is surely beyond the pale. Clearly IANAL so I’d be grateful if a lawyer could tell me whether that’s accurate.
Also, I know lie-detector results are not admissible in court but can the prosecution mention that someone refused to take a test?
No it’s not, as far as the rules are concerned. What do you think, that if a suspect is ready to make a confession, even a false one, the police will suddenly come clean and admit to all the lies they told during the interrogation, in order to reduce the pressure the suspect is feeling?
Because there’s a whole genre of shows and movies dedicated to painting police as scientists with magic tools which let them solve any case at all. And judges and juries watch those shows.
Lie Detectors are very good at finding out people who are’nt telling the truth. On the other hand, they are very good at finding people who were just nervous.
The results should only be used as a marker whether more attention is merited; not as the basis of a conviction or confession.
Isn’t there currently a far better method for detecting “Lies” anyway? Something to do with measuring the eye blink rate and micro expressions?
So if anything, lie detectors seem to be an outdated piece of technology.
In Hopt v Utah, 1884, the Supreme Court ruled that a confession is not admissible if it is obtained by operating on the hopes or fears of the accused. Telling them that their failure to pass the test means that they must have done it because the machine is infallible is nothing if not playing on their fears. Or does Hopt v Utah no longer apply?
I should have specified earlier, IANALawyer, and I apologize for not doing so.
However, my understanding is the police have the right to use attempt to use lie detectors, and the right to lie about the nature of evidence against the accused, and this has been upheld again and again in the courts. I have never heard of a single instance where the police had to … confess … to the suspect about the nature of their lies before attempting a confession. If the police have led to a suspect about evidence, I can’t imagine that it WOULDN’T operate on the hopes or fears of the suspect and perhaps result in a false confession. This would be the case especially with very serious charges, such as murder. The suspect is told there is an airtight case, maybe they throw in a little bonus like taking the death penalty off the table IF the suspect offers a full confession.
I’m sure there are suspects who simply walk in and confess. But for anybody who’s been seriously interrogated and lied to and denying all charges at first, I can’t see how a confession could possibly be anything but under conditions of fear or hope for a better outcome than a trial.
More or less. A good technician is a good cold reader. From your reaction to the test and the questions, he decides guilt or innocence. He will then point to some high point squiggle and say “The Polygraph says you lied here, who not tell me the truth.”