“If you tell a lie big enough and keep repeating it, people will eventually come to believe it. The lie can be maintained only for such time as the State can shield the people from the political, economic and/or military consequences of the lie. It thus becomes vitally important for the State to use all of its powers to repress dissent, for the truth is the mortal enemy of the lie, and thus by extension, the truth is the greatest enemy of the State.” ~ Joseph Goebbels
Pamela Meyer, the nation’s best-known expert on lying, explains how to sniff out the truth in a world of lies.
A liar often smiles subtly while telling a lie; it’s an unconscious expression of his delight in getting away with a whopper. There’s a famous photo in which Adolf Hitler was smiling while talking to British Prime Minister Neville Chamberlain at the meeting where Hitler concealed that he’d already mobilized his army to attack Poland. Other signs are when a person makes big changes in posture, like slumping in his chair or looking down. There are also verbal signals. Someone may repeat a question to stall for time. A liar may swear on the Bible or his mother’s grave that he didn’t do something; it’s what I call overconvincing or overpersuading. A person giving too much detail in a story is another example.
You’ve also said that a liar doesn’t tell a story in the same way that an honest person does.
A liar frequently cuts his ending short and doesn’t express emotion while telling his story. A person telling the truth isn’t likely to end his story abruptly, and he tends to express a lot of emotion at the end of it. He also doesn’t usually tell a story in chronological order; he jumps around a little, according to what is most prominent in his memory.