"Each of us, at least once in a life, has asked themselves: "Am I being lied to?" or "How do I say a lie and get away with it?"
Trying to find an answer to the latter, one may come up with all kinds of gimmicks and twists. Answering the first question is way more complicated. Polygraph, or 'lie detector' as journalists aptly dubbed it in the 1920s, was designed to detect and record deception. The theory is that when a person lies, the lying causes a certain amount of stress that produces changes in several involuntary physiological reactions.
A series of different sensors are attached to the body, and as the polygraph measures changes in breathing, blood pressure, pulse and perspiration, and the data is recorded on a computer. During a lie detector test, the operator asks a series of questions that set the pattern of how an individual responds when giving true and false answers. Then the actual questions are asked, mixed with irrelevant questions.
An earlier and less successful lie detector or polygraph machine was invented by James Mackenzie in 1902. However, the modern polygraph instrument was invented by John Larson in 1921. John Larson, a University of California medical student, invented the modern lie detector (polygraph) in 1921.
At the federal level alone, the polygraph is used extensively in counter-intelligence, counter-terrorism, and counter-narcotics programs in addition to criminal investigations, intelligence operations, presidential protection and nuclear materials containment. There are at least 68 countries world wide where the polygraph is used for similar applications. In the private sector, polygraph is used extensively by individuals, families, therapists, attorneys, courts, business and many other entities.
Individuals, Families, Therapists and Employers use polygraph examinations to verify statements and find out the truth on a variety of issues including infidelity, drug use, addictions, sex offenses, employee theft, criminal activities, abuse and all other matters.
Polygraph is used extensively by attorneys who wish to provide the best possible defense for their clients. Most attorneys will submit their own clients to the exam, while others will use the polygraph to verify statements made by witnesses and other parties to litigation. Now known as Psycho physiological Detection of Deception (PDD), an experienced examiner can provide evidence in connection with any type of criminal or civil matter. Our examiners have a great deal of experience working with attorneys, both in private and government practice, and have aided thousands of clients in preparing defenses that would otherwise have been unavailable to them. With the recent establishment of polygraph standards by American Society for Testing and Materials (ASTM), polygraph has gained great strides in credibility with the scientific community. These standards, approved by a combined body of experts, now provide a template for the increased acceptability of polygraph results.
Contrary to popular belief, polygraph is not per-se inadmissible in court proceedings. Admissibility standards are different in each jurisdiction. Some jurisdictions allow polygraph evidence, either stipulated or un-stipulated, some prohibit polygraph evidence altogether, and many others allow the judge to decide admissibility on a case-by-case basis. The Daubert case is presently the standard for the admission of scientific evidence, which includes polygraph. In reality, most polygraph results are used outside of the courtroom in pre-trial negotiations, plea bargaining, sentence recommendations, and witness verification or impeachment.
Local Police, U.S. Military Branches and Government Agencies such as the FBI, CIA, NSA and Department of Defense all use polygraph examinations for applicant screenings, criminal investigations and matters of national security.