To detect when people lie.
Finding information on lie detectors is easy. A police station can give you information on lie detectors. There are now lie detectors for cell phone applications. However, using the applications on phone is not a good source of proof to tell if someone is lying or not.
All will tell lie.
Lie detectors are used in law and legal issues to try to determine if someone is telling the truth or not.
No. Although lie detectors seem credible, they can be often faked to produce response opposite to what you want. The lie detectors lack the hard evidence that normal court order can provide (such as blood stain, DNA analysis, etc) and relies solely on how stressed the person is. Even when you didn't commit the crime, extremely high level of stress can tick the lie detector. Similarly, even when you did commit the crime, low level of stress can fool the lie detector. Some people say that lie detectors have a 99% chance of succeeding. It is that 1% that makes the people say "No, we don't want it."
Lie detectors, or polygraph machines as they're more officially known, are large contraptions that are filled with buttons, levers, paper, and measuring devices. They have been used for years in law enforcement to detect whether or not someone is actually lying to officials. The reason why people would lie to law enforcement officials is obvious - they committed a crime that they don't want to get caught for. Lie detectors can help solve this problem by asking a person who's strapped to a lie detector several questions and then analyzing the results. However, lie detectors still aren't permissible in court. This means that should a person fail a lie detector, they will not be able to be proven as lying in a court of law. And likewise, a person will not be able to use the results of a lie detector test to prove that they are telling the truth. This is because lie detectors can't actually detect if a person is lying. They can only tell if the person is displaying deceptive behaviour.
I would say they are not used in courts today bc their not realiable.
yes, that's what cops use. but The ones that they sell in stores don't work at all.
Travis B. Patterson has written: 'Lie detection via the polygraph' -- subject- s -: Forensic psychology, Lie detectors and detection
A: Drama B: Viewer Suspense C: To get the truth Mostly likely A+B,