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Summary: Spy the Lie: Former CIA Officers Teach You How to Detect Deception by Don Tennant, Michael Floyd, and Susan Carnicero

  • The book teaches a method to detect deception based on scientific research and the authors’ experience in the intelligence community.
  • The book explains how to identify verbal and nonverbal cues of lying and how to ask effective questions that reveal the truth.
  • The book is full of stories and examples from the authors’ careers and from current events and popular culture that make the book engaging and practical.

How can you tell when someone is lying to you? “Spy the Lie: Former CIA Officers Teach You How to Detect Deception” lays out the method used by real-life CIA officers to spot lies as they’re being told. In this book summary, you’ll learn the strategies used to root out double agents and dangerous criminals, such as key deceptive behaviors to watch and listen for, and how to apply them to your everyday life.

Learn how to spot the verbal and nonverbal behaviors that may indicate a person is lying to you.


  • Want to learn how to conduct more effective job screening interviews
  • Need to be a more effective disciplinarian
  • Are curious about the process of lie detection and the psychology behind it


CIA officer Phil Houston was conducting an interview with an important field asset, “Omar,” to determine whether Omar was an informer the CIA could continue to trust. An experienced polygraph examiner, Houston approached the interview as a “sure thing” — Omar had been a reliable asset for the CIA for 20 years.

However, once the interview began, Houston asked Omar what he thought was a routine question — “Have you ever worked for an enemy agency?” — and noticed that Omar began acting suspiciously. Houston initially dismissed it, again thinking of how clean Omar’s record with the agency was and how long he had worked as an asset for the CIA. When Houston repeated the question, Omar was still reluctant to answer. Less than an hour later, Omar admitted to being a double agent, reporting to an enemy agency the entire time he’d been working as an asset for the CIA.

Houston went into the interview with bias, expectations, and personal feelings about who Omar was and how Omar would respond. On paper, Omar was a reliable, trustworthy asset of many years, and Houston liked him. Had he not been willing to put those biases aside and explore Omar’s curious reaction to a seemingly straightforward question, he might have cleared Omar to continue working for the CIA without ever discovering that Omar was feeding information about the agency’s operations to an enemy intelligence organization.

Now, it’s fair to say that your interactions probably won’t have quite the same stakes as international espionage, but the basic principle is universal: Don’t be afraid to call a lie a lie, even if it’s coming from someone you trust.

Book Summary: Spy the Lie - Former CIA Officers Teach You How to Detect Deception

Navigating the Deception Detection Obstacle Course

We’re often our own worst enemies when it comes to being duped.

The first obstacle you must overcome is thinking that you won’t be lied to. Interactions are based on a social contract that dictates that everyone is supposed to be truthful and forthright, an idea that’s instilled in us from a young age. But statistically speaking, we lie all the time, with some research suggesting that we fib as often as 10 times a day. So while you shouldn’t enter into a conversation expecting a person to lie to you, you may need to overcome the belief that it is unthinkable that you could be lied to.

The second obstacle is believing that there are signs that show someone is lying. Most “telltale” signals that a person is being untruthful are not supported by any kind of evidence, so it’s best to forget anything you’ve ever heard about spotting a lie.

Another obstacle is plain bias. Biases are not necessarily negative, but they must be taken into consideration and appropriately managed when you’re trying to determine whether a person is lying. You have to be able to weigh factual evidence without letting how you feel about the subject get in the way.

Finally, there is the obstacle of trying to absorb every possible piece of information about a person before making your decision about their character. It can’t be done — there’s simply too much data. If you try to throw the widest net possible instead of focusing on a few key areas, you run the risk of wasting time and energy pursuing a line of evidence, such as a candidate’s posture during a job interview, that ultimately doesn’t reveal any useful information.

The Methodology: it All Comes Down to This

Polygraph tests monitor a subject for changes in four different areas to find indications that the subject is nervous or anxious, and therefore possibly lying.

You can apply the same analytical concepts of the polygraph machine to a basic verbal interview using what’s called “the model.” The model operates on a single principle: Ignore truthful behavior. That seems contradictory, but keep in mind we’re trying to spot lies, not the truth.

One important guideline of the model is timing, meaning how soon after a specific prompt, such as a question or statement given during a conversation, an untruthful behavior occurs. If a deceptive behavior is observed within the first five seconds following the question or statement, it’s very likely that the behavior is a direct response, and therefore it’s possible evidence that the subject is lying. So if you ask a co-worker, “Did you eat the leftover pizza I put in the break room fridge?” and they respond with a deceptive verbal or nonverbal cue within five seconds, you can safely assume their reaction is directly related to your question, but it doesn’t necessarily mean they ate the pizza.

The second thing to look for is clustering, which refers to the number of deceptive behaviors observed. Let’s say you’re giving a job interview and you ask the candidate, “Have you ever stolen anything from an employer?” If the candidate exhibits a single deceptive behavior in response to the question, it’s safe to make a note of it and move on. But if the candidate exhibits several deceptive behaviors, which can be both verbal and nonverbal, the probability that they are lying is greatly increased.

The Deception Paradox: Ignoring the Truth to Find the Truth

CIA officer Houston was conducting another interview, this time to determine whether a co-worker, Ronald, had stolen money from another co-worker’s purse. When Houston asked Ronald flat-out whether he had taken the money, Ronald said, “Follow me outside. I need to show you something.”

When it became clear that Houston wasn’t going to budge, Ronald said, “I wanted to show you that the trunk of my car is full of Bibles that I give away to people who need them.” This was a truthful statement that portrayed Ronald as a charitable man, but it had nothing to do with whether or not he had stolen money from a co-worker’s purse. Houston ignored this statement and pressed on with his questioning. Ronald finally admitted to stealing the money.

Learning to ignore truthful statements is vital in your ability to determine whether or not a person is being untruthful. The truthful statements in this context have nothing to do with the questions you’re trying to answer, so don’t even consider them because they won’t provide you with any useful information.

What Deception Sounds Like

There are three kinds of lies: lies of commission, lies of omission, and lies of influence. Lies of commission are flat-out, bald-faced lies, such as little Johnny insisting that he didn’t eat the last piece of cake while his face is covered in chocolate.

With lies of omission, a person tells mostly the truth but leaves out the part where they did something wrong. For example, if little Johnny says, “I went into the kitchen to get a glass of milk” and leaves out the part where he drank the milk to wash down a whole mess of chocolate cake, that’s a lie of omission.

And finally, a lie of influence is when someone uses a truthful non sequitur to influence your opinion of them and avoid answering the question. So if you asked little Johnny if he ate the last piece of cake and his response was, “I never take things without asking, and I already had my dessert tonight anyway,” that would be a lie of influence. Much like a guilty CEO insisting he has no reason to embezzle from his company because he’s already rich, lies of influence attempt to alter your perception of the liar as it pertains to the content of the lie.

When attempting to spot these three kinds of lies, look for specific deceptive verbal behaviors:

  • Did the person’s response fail to actually answer the question you asked?
  • Did the person avoid specifically denying an accusation of wrongdoing?
  • Did the person refuse to answer the question altogether?
  • Did the person repeat the question before answering?
  • Did the person make a non-answer statement?
  • Did the person turn your question into an attack?
  • Did the person excessively refer to previous statements or conversations rather than answer your question?
  • Did the person express selective memory by saying things like, “I don’t recall exactly”?

The Most Powerful Lies

The most powerful lies people tell are based around a specific type of deceptive behavior, which is making convincing statements. For example, CIA officer Houston was faced with a particularly difficult case when he was tasked with interviewing a senior government employee, “Oscar,” who was under investigation for child molestation. Houston began the interview by asking whether Oscar had had sexual contact with any of the children. Oscar responded with a forceful barrage of convincing statements, insisting, “I would never do something like that. I’m not a pervert.”

Rather than challenge Oscar, Houston responded by saying, “Hey, if I thought you were a child molester, I wouldn’t be in the same room with you.” Oscar, who had been expecting a fight, was visibly puzzled by this. Houston continued the interview, and Oscar eventually admitted to molesting hundreds of children.

When faced with a person making convincing statements, you need to be able to neutralize those statements by acknowledging them or agreeing with them, which is exactly what Houston did. If you don’t, the person is likely going to keep repeating them until they wear down your ability to see the statements for the smokescreen they are.

The Wrath of the Liar

Anger is one of the most telling examples of deceptive behavior, because it means the person feels agitated, desperate, or cornered by a particular line of questioning. For example, when former Enron CEO Jeffrey Skilling was asked why Enron didn’t reveal its complete earnings, Skilling called the interviewer an asshole. Skilling later expressed similar hostility toward the prosecution during his trial for securities fraud, for which he was convicted and sentenced to a quarter century in prison.

Anger can take the form of less obvious types of attacks. For example, during a televised interview with Diane Sawyer, Scott Peterson, who would later be convicted of murdering his pregnant wife, responded to a pointed question in a peculiar way: Sawyer flat-out asked Peterson if he had killed his wife, and Peterson smiled and said no.

Obviously, smiling while answering a question like that is suspicious, but it can also be perceived as an attack on Sawyer, meant to convey that her question was silly or meaningless and barely merited a response.

Finally, attacks can also take the form of a threat, either a threat to the questioner or a threat of self-harm. A woman being interviewed by Susan Carnicero, another CIA officer, grew increasingly agitated as the interview went on. She finally threatened to jump off the building if Carnicero didn’t stop questioning her. Even though she wasn’t threatening Carnicero directly, this is still a form of attack against the questioner, and any attack is potential evidence of a lie.

What Deception Looks Like

This summary has discussed the different types of verbal deceptive behaviors to listen for while attempting to determine whether or not a person is lying. Now we’re going to discuss some key nonverbal deceptive behaviors that can be indicative of a lie.

A behavioral pause or delay, or lack thereof, could be evidence that a person is lying. For example, if a person takes an unusually long time to respond to a simple question, or responds too quickly to a question that should generally require some thought, it could be evidence that they are either trying to think of a good lie or already have one prepared.

A verbal/nonverbal disconnect refers to a person making a statement accompanied by a seemingly contradictory nonverbal action, such as saying no while nodding. This could be evidence of a lie.

If the person attempts to cover their mouth or eyes while responding to your question, it could be an indication of a subconscious need to mask a lie as it is spoken or to avoid feeling the shame of looking you in the eyes while they lie.

When a person is lying, it often triggers an adrenaline response that redirects blood from the face and extremities to other parts of the body, leaving the face feeling cold or itchy. So any hand-to-face activity, such as lip chewing or touching any part of the face, could be evidence of a lie.

Finally, watch out for grooming gestures, such as fixing a tie or shirttail, smoothing out wrinkles in a skirt, or fussing with hair. Similarly, a person suddenly struck with the need to straighten up the area as you question them might be attempting to manage their anxiety.

Truth in the Lie: Spying Unintended Messages

Often, a person who is lying will accidentally let the truth slip in a telling phrase or choice of words. For example, in a 2009 interview on CNBC, Sanjay Kumar, the CEO of a software company accused of accounting fraud, claimed he was innocent of any wrongdoing and insisted that the discrepancies in his firm’s accounting were the result of a new method of calculating revenue. In the same interview,

Kumar referred to his explanation as “perfectly plausible” and reiterated that neither he nor his business had done anything “fundamentally” wrong. He was later sentenced to 12 years in prison for defrauding companies of billions of dollars. Kumar’s guilt and subsequent conviction are hardly surprising when you examine what he said in that interview. First of all, he tried to explain the fraud allegations as being a result of “a new method” of calculating revenue. That’s a strange way to say that you’re not doing anything wrong, because “a new method” of calculating income could absolutely refer to accounting fraud. He also said his explanation was “plausible,” which seems to indicate that he knew it wasn’t true but that it sounded like it could be. And he said that he hadn’t done anything “fundamentally” wrong, which suggests that there was in fact wrongdoing.

Unintended messages such as the ones Kumar let slip are examples of deceptive behavior and are frequently indications of lying.

You Don’t Ask, You Don’t Get

Knowing how to look for deceptive behavior is only half the equation. You also have to know what questions to ask, or else knowing the method won’t matter.

For example, let’s say you’re a police detective and you’re interviewing a man suspected of killing his wife. If you ask the obvious question, “Did you kill your wife?” the suspect will probably just say no, either because he’s innocent or because it’s the exact question a guilty person would anticipate and be prepared for. The question you asked didn’t yield enough information to work with.

However, if you ask, “What happened to your wife last night?” or “Is there any reason someone might tell us they saw you at the crime scene last night?” the suspect will be forced to give more detailed answers, which will yield more information to process.

There are many other types of questions you can use to yield valuable response from interview subjects, but in general, the shorter, simpler, and more straightforward your questions are, the better results you’ll have.

Managing Deception to Gain the Advantage

It’s important to remember that when you begin questioning someone you suspect may be lying, the advantage lies squarely with them. They have the information you want, and they’re the only person who can decide to give it to you. But simply hammering them over and over with the same question doesn’t have the same effect as it does on cop shows — the more you press on a certain subject, the more the interviewee will double down on the lie, until finally they can repeat the lie without even thinking about it. This is called psychological entrenchment, and there are a few key strategies you can employ to avoid it.

First, avoid asking negative questions, like, “You’ve never stolen anything before? Really?” That will immediately put a subject on the defensive. Use prologues to preface your key questions, such as, “I want to ask you about drug use, but let me preface by saying I personally don’t have any strong opinions about it. My only concern is if a candidate has a history of arrests or a serious addiction.” That can create feelings of understanding and camaraderie that might convince a person to be more forthright in their answers.

And finally, keep your focus broad. A person who is lying might give you a single piece of truthful information that you’ll be tempted to focus on rather than continuing to probe for the whole truth. For example, if you asked the murder suspect from the previous example, “Have you and your wife ever had a bad fight?” and he says, “Yeah we got into an argument about money a few years ago,” resist the urge to ask about that long-ago incident. Instead say something like, “OK, what other times did you two fight?” You’re avoiding the bait and keeping the questioning going.

Let’s Be Careful Out There

In the TV show Lie to Me, Dr. Cal Lightman was a “human lie detector,” an expert in identifying microexpressions, involuntary movements on a person’s face that can be indicative of certain emotions, to tell whether or not a suspect was lying. Microexpressions are indeed real things that have been studied extensively, but by no means should you go around assuming they’re ironclad proof of lying. They can be valuable pieces of information, but they have two major limitations.

First, there’s no universal microexpression for deception. A certain facial movement might be indicative of anxiety, but that’s hardly proof of a lie. Second, they tend to happen fast and without warning, so devoting the amount of focus required to catch a microexpression in the split second it appears just isn’t worth it.

Other “well-known deceptive behaviors” you might have heard of aren’t actually useful indicators of whether or not a person is lying. For instance, a failure to maintain eye contact, closed-off posture, clenched hands, nervous tension, and blushing all may seem incriminating but generally do not hold much significance.

Be careful not to jump to conclusions based on something you saw on TV, because — big surprise — TV often doesn’t get it right.

A Textbook Case of Deception

In this summary, you’ve learned how to spot deceptive behaviors in an interviewee that may indicate that the person is lying. Now it’s time to apply what you’ve learned by examining real-life interviews for signs of deceptive behavior.

You don’t have to jeopardize your personal relationships by interrogating your friends and family until you get the hang of it. Online, you can see lots of prominent public figures, who were later found to be guilty as sin, giving interviews on TV, trying to get ahead of some scandal. That would serve as perfect “homework.”

For example, after his Twitter account sent a lewd photo to a college student, Congressman Anthony Weiner appeared on CNN to push the explanation that his account had been hacked by some prankster and that the photo hadn’t been sent by him. If you watch that interview or read a transcript of it, both of which are readily available online, you can analyze each of Weiner’s responses and find a staggering number of deceptive behaviors, including refusal to answer the question, attacking the interviewer, and giving a non-answer. Weiner admitted he had tweeted the photo himself, and that he had a long history of sending unsolicited images to young women, four days after the CNN interview.

Watch similar interviews involving pre-fall politicians and celebrities, and see how many deceptive behaviors you can spot.


We experience hundreds of thousands of human interactions throughout the course of our lives, both personal and professional. Because of the staggering number of those interactions, and the fact that we’re conditioned to give people the benefit of the doubt, we are extremely vulnerable to deception. Being able to spot that deception is vital, because it can have an immediate and profound effect on our lives, whether we’re trying to determine if a co-worker is a thief or figure out if a teenage son is doing drugs. You can train yourself to watch for a number of significant deceptive behaviors, both verbal and nonverbal, when attempting to evaluate a person’s truthfulness.

But evidence of deception is not proof of deception. Knowing deceptive behaviors and verbal cues can only take you so far. If that co-worker is exhibiting all the textbook signs of lying but won’t fess up to stealing money from the register, it’s up to you to weigh the significance of the deceptive behaviors you spot and make your own judgment.

About the author

Philip Houston, Michael Floyd, and Susan Carnicero are all former CIA officers who specialized in polygraph examination during significant portions of their careers. Don Tenant is an award-winning business/technology journalist who began his career as a research analyst with the National Security Agency.

Philip Houston, a twenty-five-year veteran of the Central Intelligence Agency and a recipient of the Career Intelligence Medal, is a nationally recognized authority on deception detection, critical interviewing, and elicitation. He has conducted thousands of interviews and interrogations for the CIA and other federal agencies, and is credited with developing a detection of deception methodology currently employed throughout the U.S. intelligence and federal law enforcement communities.

Michael Floyd is a leading authority on interviewing, detection of deception, and elicitation in cases involving criminal activity, personnel screening, and national security issues. In a career spanning more than thirty-five years, he has served in both the CIA and the National Security Agency, and founded Advanced Polygraph Services, where he conducted high-profile interviews and interrogations for law enforcement agencies, law firms, and private industry.

Susan Carnicero, a former security officer with the CIA specializing in national security, employment, and criminal issues, is an eminent authority on interviewing, detection of deception, and elicitation. Trained as a forensic psychologist, she is the developer of a behavioral screening program used extensively in both the public and private sectors, and is currently involved in conducting high-level screening interviews within the U.S. government.

Don Tennant is a former National Security Agency analyst and business/technology journalist. As editor in chief of Computerworld, he won a variety of national journalism awards, including the Timothy White Award for Editorial Integrity and the Jesse H. Neal National Business Journalism Award from American Business Media.


Psychology, Nonfiction, Self Help, Business, Science, Personal Development, Communication, Reference, How To, Characteristics and Qualities, Self-Improvement, Relationships, Interpersonal, Social Interactions in Relationships, Personal Growth, Health, Fitness and Dieting, Counseling, Popular Applied Psychology, Popular Psychology Personality Study, Communication and Social Skills

Table of Contents

Acknowledgments vii
Introduction: Welcome to Our World 1
1 The Difficulty We Have in Calling Someone a Liar 7
2 Navigating the Deception Detection Obstacle Course 15
3 The Methodology: It All Comes Down to This 27
4 The Deception Paradox: Ignoring the Truth in Order to Find the Truth 43
5 What Deception Sounds Like 51
6 The Most Powerful Lies 73
7 The Wrath of the Liar 81
8 What Deception Looks Like 93
9 Truth in the Lie: Spying Unintended Messages 103
10 You Don’t Ask, You Don’t Get 119
11 Managing Deception to Gain the Advantage 139
12 Let’s Be Careful Out There 149
13 A Textbook Case of Deception 159
14 Okay, So Now What? 189
Appendix I Suggested Question Lists 201
Appendix II A Sample Narrative Analysis Based on the Model 213
Glossary 231
About the Authors and Writer 243
Index 249


The book is about how to detect deception in everyday situations using a methodology developed by Philip Houston, a former CIA officer and one of the co-authors. The authors claim that their method is based on scientific research and decades of experience in the fields of counterterrorism and criminal investigation.

They explain how to identify deceptive behaviors, both verbal and nonverbal, that people tend to display when they lie. They also teach how to ask effective questions that elicit the truth and avoid common pitfalls that can lead to false conclusions. The book is full of anecdotes and examples from the authors’ careers, as well as from current events and popular culture, that illustrate their points and make the book engaging and entertaining.

The book is a fascinating and practical guide for anyone who wants to improve their ability to spot lies and uncover the truth. The authors are credible and authoritative, as they draw from their extensive experience in the intelligence community and share their insights and secrets with the readers. The book is well-written and easy to follow, as it uses clear language and simple concepts that anyone can understand and apply.

The book is also very relevant and timely, as it covers topics such as terrorism, politics, business, media, relationships, and more. The book is not only informative, but also fun and enjoyable, as it contains many stories and examples that are both amusing and enlightening. The book is a must-read for anyone who wants to learn how to spy the lie and become a better communicator, decision-maker, and observer of human behavior.

Alex Lim is a certified book reviewer and editor with over 10 years of experience in the publishing industry. He has reviewed hundreds of books for reputable magazines and websites, such as The New York Times, The Guardian, and Goodreads. Alex has a master’s degree in comparative literature from Harvard University and a PhD in literary criticism from Oxford University. He is also the author of several acclaimed books on literary theory and analysis, such as The Art of Reading and How to Write a Book Review. Alex lives in London, England with his wife and two children. You can contact him at [email protected] or follow him on Website | Twitter | Facebook

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