If a lie detector can make mistakes and be deceived, then why is everyone so afraid of him and believe in his infallibility? All thanks to PR. The lie detector is well advertised all over the world, so many people spread a lot of money to use this unit.
To deceive the lie detector can many people, for example, social psychopaths can easily enter this device in error. Social norms social psychopath seem different, so thinking this person could believe that I did everything right and nothing broke. Also lie detector can fool teenagers, or elderly people, they can answer the question, not quite realizing it.
Good actors can also easily fool the detector, because if a person strongly believes in his lies, he will begin to appreciate it as the truth. If the person is not an actor, not a child and not a man, and is psychologically sick, then it can also fool a lie detector. He just needs to practice a little in a lie.
A few ways to cheat the lie detector: you can just the evening before the session to grab a drink. In this case, on the morning of the person's response will be chilled that will confuse the camera. It is also possible to use a sedative or something, which will reduce the amount of produced adrenaline.
Fool the detector is due to the complete control of their emotions. For this you need to focus all their attention on something extraneous, in this case the person begins to respond to the machine. This method actually works, but it is not very safe – because the inspectors can see the detachment and bring people out of this state.