SO, you think you can pick a liar?
Covert operations specialist David Craig can.
The 48-year-old former Mackay man, who's been working in his field for 21 years, says there are more Pinocchios among us than we think.
"I think (people lie) about once in every 10 minutes of conversation," Mr Craig said.
The reasons people lied was to avoid embarrassment, make a positive impression and to avoid punishment, Mr Craig said.
"Lying is quite regular and acceptable, it's just we (think) that lying is a terrible thing," he said.
"There's polite and good reasons for people to be telling a lie. It's not always a sinister thing.
His book, Lie Catcher, teaches people how to detect a liar through a 'magic' lie detection model.
"Magic is the acronym: M is for motivation, you need to find out has this person got the motivation to lie to me," he said.
"The next one is A, to ask for control questions; and they're questions that either I know the answers to or that you wouldn't lie about.
"I'm mentally cataloguing what you're doing with your body, eyes and speech.
"Then I'll ask G, which is the guilt questions.
"For I, I'm looking for indicators... I look for any change... I might see a couple of quick flicks of the eye or looking away and that any change (when answering the guilt questions).
"C is to check again, so you've got to run through that process again to make sure you got it right.
"It's actually harder to tell if someone close to you is lying... over confidence can work against you... and you want to believe people that you like."
The father of four said he didn't always have his "lie radar" on but turned it on when it was necessary.
"You only turn it on when you have to, because it's actually quite exhausting.
"When it's important I do; what websites have they been on (or) what time did you come home last night."
Mr Craig was unable to reveal who he works for or a career highlight, because it was 'secret squirrel' business.
"It's a lot of covert infiltration and surveillance.
"I just think it's a really fascinating area to be involved with.
"I like the idea of bad guys getting caught, there's no better way to do that than (in this job)," Mr Craig said.
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