For techniques on spotting whether your nearest and dearest are telling you fibs, look no further than this University of Michigan study.
Researchers studied 118 video clips to determine behaviour exhibited by dishonest individuals including testimonies and YouTube videos in which interviewees were asked their opinions on films that didn't exist.
So what were their findings? Well, if someone's talking to you while frantically waving their hands and giving you more eye contact than usual, chances are you're probably being duped.
They also found that other surefire signs include scowling and lots of head-nodding.
It should be noted, however, that similar gestures were also used by truth-tellers – albeit a smaller percentage (sixty per cent looked into the interviewer's eyes compared to seventy per cent of liars).
As a consequence, this study does paint a vague picture of dishonesty without really confirming anything - although researchers hope to develop lie-detecting software from the study.
So if you're a compulsive liar and you don't want to be found out, this is probably the behaviour you should avoid.