Book SummarySpy the Lie, by Philip Houston, Michael Floyd, and Susan Carnicero

1-Page Summary1-Page Book Summary of Spy the Lie

Have you ever had the feeling someone was lying to you...even when every word from their mouth seemed true?

In a world where truth and lies seem always to be intertwined, Spy the Lie gives you the tools to cut through distracting...

Spy the Lie Summary Introduction: Why You Need a _System_ to Detect Deception

You might wonder why you need a system to detect deception—like most people, you likely feel that you can tell when someone’s lying to you. However, the authors note, it’s impossible for anyone—even intelligence community professionals—to simply know whether someone is lying. The authors give two reasons for this: human bias and people’s tendency to hide deception within truth.

Reason #1: Humans Are Biased Toward Believing Others

Even when you have good reason to think someone is lying to you, your inherent desire to believe them can make you miss or excuse signals of their deception. You may even be biased to believe certain kinds of people are trustworthy—a Supreme Court justice, your grandmother, or the manager of your child’s daycare—although people from all walks of life can be liars.

(Shortform note: Why do we have a tendency to believe others, if it doesn’t always help us? In The Liar in Your Life, psychologist Robert Feldman explains that your brain is hard-wired to assume others are honest. This served an evolutionary purpose: Someone who’s not constantly...

Spy the Lie Summary The Basics of the System

In his CIA career, Houston interviewed people using a polygraph machine, a device that charts a person’s physiological responses to questions. As Houston gradually learned which verbal and behavioral signals reliably linked to deceptive responses, he created a System to replicate the polygraph’s functionality in two steps:

1. Ask someone (we’ll call him the “interviewee”) a question. This stimulus prompts the interviewee’s verbal response and involuntary physical reactions.
2. Watch and listen closely to your interviewee’s reactions and responses. You’ll look for elements of their response that suggest they might be deceiving you or having a physiological reaction to your question. (We’ll cover telltale verbal and behavioral signs of deception in the final section of the guide.)

(Shortform note: Polygraph machines are often called “lie detectors,” but they don’t actually detect lies. Instead, polygraph machines usually measure changes in several bodily functions: blood pressure, heart rate, respiration, and skin conductivity. However, these increases denote spikes in anxiety—which aren’t necessarily...

Spy the Lie Summary Step 1: Ask Your Interviewee Questions

Now that you understand the basics of the System, let’s explore the details of using it. The first step is to ask the interviewee a question—creating a stimulus that they’ll have to react to. In this section, we’ll first cover the most effective methods of questioning, then explain behaviors to avoid when asking questions.

Ask the Right Questions

The authors advise that certain types of questions are more effective than others. The “right” kinds of questions conserve your mental energy—saving it for the intense focus required in observing both the verbal and behavioral aspects of your interviewee’s response. Effective questions also increase the mental energy your interviewee must spend on his responses—making it harder for him to create false details, keep his story straight, and figure out ways to get around directly answering you.

(Shortform note: It can be difficult to define or quantify the mental energy you use in a conversation, but Cognitive Load Theory (CLT) researchers suggest an answer: They say you can only hold three to seven pieces of information—which can range from a single word to a...

Spy the Lie Summary Step 2: Listen and Watch For Signs of Deception

Following each question, you’ll apply the second part of the System: simultaneously watching and listening for verbal and behavioral signs of deception in your interviewee’s response. Recall that the first sign must happen within five seconds of your question, and that you’re looking for a cluster: two or more signs.

We’ll now cover the specific verbal and behavioral signs that the authors say to watch for, as well as how each sign can signal deception.

Verbal Signs of Deception

Verbal signs of deception are certain things the authors have found guilty people often say in response to questions—usually in a bid to buy time or manipulate you into liking them.

The authors provide four broad categories of verbal signs to look out for: “inappropriate” responses, failure or reluctance to answer, qualifier-heavy answers, and generally suspicious responses. There are numerous specific signs within each category that you’ll look for and count when identifying clusters. Let’s explore each category and its signs now.

Verbal Category 1: “Inappropriate” Responses

Inappropriate responses don’t make sense given the tone or subject of your conversation. The...

Shortform Exercise: Examine Your Biases and Prepare to Use the System

The authors assert that everyone is capable of deception. To get comfortable testing others for signs of deception, you must first rid yourself of the belief that someone else would never lie to you. In this exercise, reflect on why you might trust others by default and why you may need to use the System.

Identify a situation where you might instinctively trust a stranger. Why are you inclined to do this?