Former FBI agent of 21 years: These are the 8 biggest 'warning signs' that reveal a dishonest person

Every person has a tell. Your friends, co-workers, family members, partner and boss may actually be revealing their true intentions, but shrouding them in clever disguises.

As a retired FBI special agent and former chief of the Counterintelligence Behavioral Analysis Program, I spent 21 years defeating people whose sole intention was deception and trickery. Through years of trial and error, I recognized certain key patterns and learned how to "size people up" — or predict what others will do, and trust them accordingly.

Here are the biggest warning signs that reveal a dishonest person:

1. They speak in absolutes, such as 'always' and 'never.'

Absolutes are meant to support a point of view, but they're rarely true and can easily incite denial and opposition.

When someone says, "You never compliment me," for example, they're just begging you to say: "That's ridiculous! I remember giving you compliments!" Even when you know that someone is just exaggerating, it can be hard to tell if know it. When absolutes go unchallenged, they have a perverse tendency to be reborn as the truth.

People who are trustworthy tend to use words that soften absolutes, such as "usually," "often," "probably," practically," "sometimes," "frequently" and "generally."

2. They brag by downplaying their accomplishments.

A lot of people think they know how to brag artfully, but really don't. Some wait for the right moment in a conversation to casually toss in their 15 seconds of self-promotion — as mere information, a pertinent example or a flash of amusing recollection. And when you give them the kudos they're looking for, they brush it off.

If they name-drop, they mention the "Big Name" in a cluster of unknowns, as if they're not even aware of their status-seeking. Another example might be the co-worker who always tries to reassure that you'll be able to do something better than they did, in the guise of encouragement. But their primary goal is to remind you of how great are — as you struggle to do it.

3. They try to please you by judging people you both know.

They imply that you're better than those other people, otherwise they wouldn't be confiding their disapproval. They give you opportunities to jump in with your own disapproval for those people, as if it's a healthy form of bonding.

Meanwhile, all you're thinking is: me ?

4. They're highly defensive.

Dangerous trait! And>5. They love to debate.

I'm not talking about an exchange of rational ideas. I'm talking about the hyperemotional dogfights that now dominate opposing discussions everywhere from "The Real Housewives of New Jersey" to political debates.

Debating tactics are just a string of tricks that can be shockingly ineffective in manipulating people. Some of the worst include: Attacking people instead of ideas, using insinuation and innuendo, playing>6. They talk too much and say too little.

It's usually because they're trying to hide something or just don't have anything to say. So they try to substitute quantity for quality, especially by dropping meaningless buzzwords like "negative growth," "thought leader" or a currently ubiquitous cliche du jour: "strategic planning" — as if a regular plan is just a wish list.

In contrast, — a gifted speaker and Nobel laureate in literature —>7. They don't know how to apologize.

Apologizing is pretty easy. You say, "I'm sorry." And that's it. Unfortunately, it's something you'll rarely hear from a dishonest person. They'll say, "I'm sorry. …" Then comes the about-face, usually fueled by an accusation: " I>8. They display uncomfortable body .

Nonverbal communication is the ultimate dead giveaway. Here are some signs that indicate a person is uncomfortable with what they're saying:

  • Unlike with a genuine smile, the corners of their mouth don't go up, but are pulled straight back. The smile doesn't include their whole face, and their brows are often furrowed.
  • Their head angle is tilted slightly backward, rather than off to either side. And they literally look down their nose at you.
  • People who are truthful have their eyes wide open. The eyes of a dishonest person, however, are somewhat lidded and tend to be locked on you, without much movement.

(When you see these signs, it's wise — and often kind — to give them special attention about they feel uncomfortable.)

These expressions are the most revealing if they happen frequently, but not all the time. The times when they don't happen give me a baseline for evaluation. Then, when I do see these signs, I have good reason to analyze them for other tells that show how they really feel.