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

Houston, Floyd, and Carnicero present their deception detection methodology, which emerged from Houston’s experience as a CIA polygraph examiner. The authors explain that polygraph machines do not actually detect lies but rather measure physiological responses to questions. After Phil Houston began to work as a polygraph examiner in the late 1970s, he started to question why interviews in everyday situations lacked the same analytical discipline that polygraph examiners apply when correlating questions with physical reactions. The methodology outlined in the book stems from this insight.

The methodology consists of one strategic principle and two practical guidelines. The strategic principle states that to detect lies effectively, one must ignore truthful behavior and focus only on deceptive responses. While this approach seems counterintuitive, the authors argue that paying attention to honest responses distracts from identifying actual deception.

The first guideline concerns timing. When someone asks a question, any deceptive behavior must begin within the first five seconds of that question being asked. The authors base this timeframe on research showing that people think approximately 10 times faster than they speak. Therefore, if suspicious behavior occurs more than five seconds after a question, it likely relates to other thoughts rather than the specific question asked.