One of our instructors at the academy told us that half of everyone we speak to will be lying and the other half will be hedging. That pearl has helped me in my job more than any other. The lies run the gamut from "I didn't hit her at all," to "The burglar stole my original Picasso." I have learned to ask all of my victims what they think the suspect might say about them in order to get a clearer picture of what actually happened. This allows people to present the story through the "lies" of the suspect without admitting to the truth of what their part was.

One lie I can always spot is "two beers." When I hear that from a driver that I've stopped for erratic driving, then I know that I've hit the jackpot. I don't know why 90% of drunk drivers say they've had two beers. It's like there is some sort of genetic code that dictates this answer. They could say they've had two glasses of wine or one martini but they rarely do. I don't mind though because it just makes my job easier.

If I ask someone to explain the contraband in their possession or whatever and they start talking about "some guy" who gave it to them — Bingo! I am constantly amazed at the lack of foresight that criminals display when the jig is up. My favorite example along these lines was a guy I arrested for stealing a bicycle. I knew he had stolen the bicycle but I could not prove it at the time. When I patted him down, I found a bunch of tools in his jacket. I asked him about the tools and he told me, "I like to go around at night and fix bicycles." He could have said anything, but he chose to describe himself as being the bicycle fairy. This allowed me to arrest him for possession of burglary tools, instead of having to let him go.


I tend to think someone is lying when the answer doesn't seem to jive with the information that you have, i.e., if you know the area that the person is talking about. For example, say a person crossing the Canadian border between Windsor, Canada and Detroit, Michigan states that he went over a bridge and under a tunnel on the way into Canada. Wrong. It's one or the other, as we used to say at School of Communications at the American University in D.C. under the cloak of "deep background".


I can tell that a student (or anyone, for that matter) is lying by a combination of tone and face, so it has to call attention to itself. Students do this through tone and a face that has a sort of removed, inauthentic quality. It's almost like they're talking talk, they're not just talking. They're presenting and wondering if it will fly. Specifically, they use what they think I will accept. For example, I have said, "Did I say it was okay for this paper to be late?" because I can't remember half my extras granted to students. When they tell a story, then, about how I promised … I can usually tell if I did or didn't.


The first thing you do a lot of times is investigate the client's story. You can get burned if you don't. I had one woman who called me who said she thought her husband was having an affair, and would we investigate? We don't often do this kind of work. The next call, she says, he's not really her husband. He's really her boyfriend. The next call she says, oh, and he's married …

A lot of what I use to tell if a person is lying is non-verbal which, in a lot of ways, is more reliable than the words they're using. For example, I'll ask some routine questions, "Where do you work?", "How long have you worked there?", "What's your boss's name?", etc. And as I'm doing this, I'm watching the person, trying to get their non-verbal baseline behavior. How do they sit? What gestures do they use? Do they groom themselves? How much eye contact do I have with them? Then, when I have that information, I'll ask a more provocative question and you see whether their non-verbal cues change. So after all the biographical questions, if it's a theft case, I'll ask, "Joe, do you know who did this?" and then I watch to see if Joe crosses his legs or looks away or becomes suddenly incoherent.

While these physical cues are different for each person, there are some common ones that seem to be pretty accurate. I always conduct my interviews with the chairs facing each other, with about 48 inches (this is sort of the halfway point between public and personal space) and with nothing in between us. A person who's lying or withholding the truth will try to make a barrier between us. They'll stick their legs way out, or they'll cross their arms in front of their body. They're trying to make a shield.

The other cue that seems to be true is that a right-handed person, when they're trying to recall information (such as an old employer's name) will typically look to their left. On the other hand, if they're trying to edit what they're telling you, they'll more typically look to the right. Reverse this for a left-handed person. I've found this to be pretty accurate.

There are also verbal behaviors. If you're investigating a theft and ask an employee, "Do you know why I'm here?," an honest person will say, "Because something was stolen." A dishonest person, or someone who's involved will say something vague like, "Oh, you're here about that thing that happened." Or they'll give you way too much detail. "It couldn't have been me because at 3:15 I went to McDonald's and then I went here and here and here."


People don't lie to me as much as they conceal. No professional is going to tell me an out-and-out lie, although he might repeat something his client said without knowing if it's true or not. But they have to deal with us again and again, so they don't want to make us mad.

The two best clues that someone is lying are that either the client is drowning you in information that you don't need, or there are odd gaps in a run of information. For instance, you ask for copies of loan documents for the year and you only get information for the middle of the year, not the beginning or end. None of the classic "does he look you in the eye" stuff works since I mostly deal with professionals.


The most common lie is about how much money a client has. In our society, a person's worth is equated with their income. People then will inflate the amount they can pay. This is particularly true with renters. They just don't want to admit, this is what I can afford. The biggest tip is when people are vague and won't name a number. They'll say, "I'll just pay whatever it's worth," or "Cost isn't important."

Most of the lies I deal with revolve around loyalty. If an agent puts a lot of time into working with a client and then finds out that the client has been working for several other agents — and sometimes puts in a bid through another agent — that's about the worst thing that happens to us. All of our time and effort has been wasted.

A common property-seller lie is about motivation: that they're not eager to sell. For a renter, it's why they want the place. If I get a successful commodities trader who wants a small, furnished apartment on a short lease, I know — almost always — that he's having a trial separation.


People lie to us all the time and they don't know it. Even if there are signs in the airport, most people have no idea what they can and can't bring into the country with them. Often they realize while they're trying to bring their luggage in that they have something they're not supposed to have. Cigars or ivory or even medicine. The people who are genuinely ignorant probably get away with more because they don't know enough to be nervous. Nervous people answer your questions too fast and in too much detail. They also get aggressive and defensive. That's a dead giveaway. Of course, getting aggressive with any Customs official is a bad idea. In almost any country in the world, we're the people who can make you miss your plane — if you give us a hard time. Just be calm and answer the questions you're asked. Don't start yelling about how you're a U.S. citizen or you pay my salary, because I don't care.


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