The Polygraph Exam is the correct term for the more commonly known title ‘lie detector test’

A polygraph exam (or lie detector test) uses an instrument (commonly referred to as the lie detector) that monitors and records various changes in the Sympathetic and Parasympathetic Nervous Systems while a series of carefully designed questions is asked of the person who is attached to the instrument.

The Polygraph Examiner is the qualified person conducting the exam, while the Examinee is the term used for the test participant.

Our polygraph examiners only use and operate polygraph equipment, which fully complies with the APA and BEPA requirements. This equipment is capable of continuously recording:

  • Thoracic and abdominal movement associated with respiration 
  • Changes in electro-dermal status consequent to the activity of the sweat glands 
  • Cardiovascular activity relating to changes in pulse rate and blood pressure 
  • It also includes a separate data channel specifically designed to record covert body movements

A polygraph exam (or lie detector test) can take anywhere between 90 minutes and 3 hours to complete (the average being around 2 hours).

The longest part of the process is the pre-test interview which takes on average 45 – 60 minutes. 

We are committed to providing a world class service to our clients and all examinees will be treated with the utmost respect and dignity.

Design of Examinations

The following is an overview of the different phases involved in a Polygraph exam.

Pre-Test phase:

  • Introduction of Polygraph Examiner 
  • Examinee to sign Consent forms 
  • Overview of polygraph process 
  • Pre-test questions relating to purpose for taking the test
  • Any admissions with responses fully documented 
  • Key questions explained to examinee until they are comfortable

Test Phase:

  • Polygraph equipment attached to examinee’s body 
  • Acquaintance test to familiarise examinee with procedure
  • Actual test with no more than four relevant questions 
  • Polygraph equipment removed from examinee’s body

Post-Test Phase: 

  • Analysis of Polygraph charts 
  • If the examiner has rendered an opinion of Deception Indicated (DI) or Significant Responses (SR) further questions will be asked 
  • Post-test interview

Examination Report

Whatever the outcome of the examination, a full written report will be issued for each examinee. These written reports will be sent to the client within 24 hours (1 working day) of the final exam being conducted.

The report will contain all pertinent information derived from the polygraph exam.

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