Mark McClish is a retired Supervisory Deputy United States Marshal. He spent nine years teaching interviewing techniques at Marshals Service Training Academy. During this time, he developed the Statement Analysis® techniques to detect deception in a verbal and written statement.

Mark retired from the Marshals Service in 2009 and started Advanced Interviewing Concepts. His company provides interviewing skills training and assists investigators in analyzing a suspect’s statement. Mark currently gives presentations on his Statement Analysis® techniques throughout the United States. He is the author of the books “I Know You Are Lying” and “Don’t Be Deceived.”