How to Tell If Someone Is Lying From a Psychologist Who Trains the FBI David J. Lieberman, Ph.D., is a psychotherapist who teaches law-enforcement agents to be human lie detectors. These are some of his science-backed techniques. Previous Article When 'Who You Know' Can Actually Hurt Your Entrepreneurial Success. Here's Why. Next Article FTX Investors Sue Celebrities Including Tom Brady and Larry David For Endorsing Exchange