Lie Detector/Polygraph Examination Services
A polygraph (commonly referred to as a lie detector) is an instrument that measures and records several physiological responses such as blood pressure, pulse, respiration and skin conductivity while the subject is asked and answers a series of questions, on the basis that false answers will produce distinctive measurements. The polygraph measures physiological changes caused by the sympathetic nervous system during questioning. Within the Federal Government, a polygraph examination is also referred to as a psycho physiological detection of deception (PDD) examination. Several other technologies are also used in the field of lie detection, but the polygraph is the most famous.
When the truth is essential, EPIS will deliver.
The polygraph test is the worldwide standard in determining if an individual is being honest.
Our polygraphists have the certification, experience, and training to conduct court admissible polygraph examinations. Information is verified based on analog and digital testing in connection with interviews and questioning.
Polygraph equipment notes physical changes that indicate that a subject is being dishonest. At the conclusion of a polygraph, examination this information is used to determine a professional opinion based on this concrete evidence.
Polygraph examinations are available for the following situations and are conducted in full compliance with the Employee Polygraph Protection Act:
- Employee Theft.
- Law Enforcement and Government Internal Investigations.
- Pre-Employment Screening.
- Criminal Investigations.
- Civil Investigations.
- Sexual Harassment.
- Drug Usage Accusations.
- Domestic Investigations.
What is involved in taking a polygraph examination?
A polygraph examination usually takes between 2-3 hours beginning to end and consists of three different phases – pre-test interview, collection of charts and analysis of charts.
There are two types of instrumentation, analog and computerized. With EPIS, we use computerized instrumentation.
A typical polygraph test starts with a pre-test interview to gain some preliminary information which will later be used for Control Questions. Then our agent will explain how the polygraph is supposed to work, emphasizing that it can detect lies and that it is important to answer truthfully. Then a “stim test” is often conducted: the subject is asked to deliberately lie and then the tester reports that he was able to detect this lie. Then the actual test starts. Some of the questions asked are irrelevant, others are probable-lie Control Questions that most people will lie about and the remainder are the “Relevant Questions “, that the agent / private investigator is really interested in. The different types of questions alternate. The test is passed if the physiological responses during the probable-lie control questions are larger than those during the relevant questions. If this is not the case, the tester attempts to elicit admissions during a post-test interview, for example, “Your situation will only get worse if we don’t clear this up.
During the pre test interview the examiner will explain how the polygraph works, discuss the issue, develop, and review all questions to be asked on the polygraph test. This stage is normally the longest to complete and will take anywhere between 45-90 minutes.
Collection of Charts – During this phase the subject will be attached to the polygraph. The question set which was developed during the pre-test interview will be asked three or 4 times.
Analysis of Charts
Once the examiner has collected the charts he will analyzes the results before giving a decision as to the subject’s truthfulness or deception.
The specialized nature of polygraph means that only a few companies exist in USA, which can offer this service.
Admissibility of Polygraph Examination
In 2007, polygraph testimony was admitted by stipulation in 19 states, and was subject to the discretion of the trial judge in federal court. The use of polygraph in court testimony remains controversial, although it is used extensively in post-conviction supervision, particularly of sex offenders. In Daubert v. Merrell Dow Pharmaceuticals (1993), the old Frye standard was lifted and all forensic evidence, including polygraph, had to meet a new standard in which “underlying reasoning or methodology is scientifically valid and properly can be applied to the facts at issue.” While polygraph tests are commonly used in police investigations in the US, no defendant or witness can be forced to undergo the test. In United States v. Scheffer (1998), the U.S. Supreme Court left it up to individual jurisdictions whether polygraph results could be admitted as evidence in court cases. Nevertheless, it is used extensively by prosecutors, defense attorneys, and law enforcement agencies who believe in its utility. In the States of Massachusetts and Maryland, it is illegal for any employer to order a polygraph either as conditions to gain employment, or if an employee has been suspected of wrongdoing. The Employee Polygraph Protection Act of 1988 (EPPA) generally prevents employers from using lie detector tests, either for pre-employment screening or during the course of employment, with certain exemptions.
In the United States, the State of New Mexico admits polygraph testing in front of juries under certain circumstances. In many other states, polygraph examiners are permitted to testify in front of judges in various types of hearings (Motion to Revoke Probation, Motion to Adjudicate Guilt).
In 2007, in Ohio v. Sharma, an Ohio trial court overruled the objections of a prosecutor and allowed a polygraph examiner to testify regarding a specific issue criminal examination. The court took the position that the prosecutors regularly used polygraph examiner to conduct criminal tests against defendants, but only objected to the examiner’s testimony when the results contradicted what they hoped to achieve. Dr. Louis Rovner, a polygraph expert from California, tested the defendant and testified as an expert witness both at a pretrial admissibility hearing and at trial. The defendant, who had been charged with sexual battery, was acquitted.