Some of the more obvious signs of lying include different answers when you repeat a question, and hesitation in answering. You also can watch for eye movements that differ from the usual. Be careful with these individual signs, since shifty eyes may be normal for some people, even when telling the truth. Compare eye movements and other behaviors to their known tendencies.

There are other signs of lying you can learn, but perhaps it is more useful to learn how to get the truth out of a person. That’s what the rest of the tips below cover.

Motivation

Determine whether the person is more motivated by rewards or fear. You may have to ask about events in her past to determine this. Then tailor your approach accordingly. Suggest or hint at good things that will come from telling the truth, or bad things that will come from lying. You might even do both.

Build Rapport

Suppose you are trying to get some information about your friend - who may have lied to you - from his brother, who you don't know well. The first thing you would want to do is build rapport. If he mentions a movie he liked, you say, "Yeah, I loved that movie." You continue to find things you have in common with him and then start working any relevant questions into the conversation.

Rapport creates trust. Other ways to create rapport include sitting like the person you are talking to, using the same words and expressions he uses, and talking at the same speed. The more he feels that you are just like him, the more likely he is to open up and talk.

Use Subliminal Persuasion

Subliminally reward the subject whenever you know he is telling the truth, and quietly "punish" him when he lies or withholds information. This might be as simple as a compliment and a smile when he tells the truth, and an uncomfortable glare when he lies. If your acting ability is good enough, you might change your whole demeanor in a second according to whether he is cooperating or not.

Of course, you'll have to have a pretty clear idea of when he is lying and when he is telling the truth for this to work. But this will work when done right. Anyone who consistently feels stressed when lying, and relief or pleasure when telling the truth, will unconsciously feel a greater inclination to tell the truth.

Make Assumptions

You can sometimes get a confession by making assumptions about what you think happened. For example, suppose you suspect a friend of saying some nasty things about you. If you ask, he will lie.

Instead, you start with, "I think I know why you said those mean things about me, but if you're my friend you can at least tell me why you said them."

If your friend did say things about you, and is convinced that you know this, he will usually offer some explanation at this point, confirming his guilt. If he hesitates after you say this, he may be weighing his options, indicating that he did say something about you. He now has to decide to lie and risk losing the friendship, or acknowledge what he did. If he is truly innocent, he is likely to immediately say so.

The signs of lying are a good thing to know, then, but it can also help to know the techniques for getting at the truth.