Can lie detector devices be trusted 100%?

No.

Lie detection devices rely on reading various body signals (sweaty-palms, racing heartbeat) that happen when you lie. And these signals can be wrong for a lot of reasons.

First off, if you don't think that you are lying, then there is no "lie" to detect. The machines can not tap into some huge library of truth. They only measure the human body. So if you're not lying but wrong, the machine won't know.

Second, some people don't give off these signals when they are lying. They've either trained themselves not to, or they are sociopaths, or whatever. No physical cues, nothing for the detector to pick up. And flawed answers.

Third, some people give off these signals whether or not they are lying. This is one way people learn how to beat these tests. If your heart races on every question - true or false - then there is no way to determine when your heart is racing because you were digging your fingernails into your palms and when your heart is racing cuz you're lying.

Sorry. They just aren't 100% reliable. That's why they aren't allowed as evidence in court.

No, they can not be trusted 100%. the fundamental basis that this "lie detector" uses is body resistance changes. It is based on the basic idea that if you are telling the truth, your body remains cool and calm, while if you are lying, your body sweats. The problem is, some people will sweat more from the truth than from a lie because of what they happen to be feeling at the time.

No, like almost everything in life, lie detectors cannot be trusted 100%.

No, Not a 100%

No, from what I heard lie detectors aren't always accurate. IT's been said that Lie detetors don't catch every lie but maybe you could look it up on teh internet for more answer. Hope that helps.

i've seen on tv shows that there are ways to trick lie detectors. it has to do with your state of mind. if you are telling the truth but you seem nervous then it will probably say you lied, but if you are lying and you are completely calm then it would most likely say that you are being truthful. but this isn't always true, for the most part they are pretty accurate.

NO, because some people are trained to beat a lie detector test. It can be deceived.

No .... Not admissible in court. some can pass but not be truthful especially those trained to , and pathologically prone to lie

It's not a lie, if you believe it - George Costanza

probably not. i think the cheap ones arent always right but those big expensive ones are probably more accurate