Polygraph ProceduresENGLISHFRANÇAIS

Polygraph Procedures

Galianos Polygraphe Expert is mandated by government, law enforcement and security organizations, the legal community, the private sector and private citizens to administer polygraph examinations for the purpose of verifying the truthfulness of statements by persons regarding specific issues that are the object of an investigation.

Once the services of the firm have been retained, the polygraph examiner will hold a meeting or have a telephone conversation with the client during which he or she will obtain the background information and case facts of the specific issue under investigation. It is crucial that the client provide the examiner with solid information for it will serve as the basis for the polygraph examination. All case facts must be previously established by way of a thorough investigation.

The polygraph examiner will then schedule a mutually agreed upon time with the client for the polygraph examination to take place.


Polygraph Examination

A polygraph examination consists of three separate and distinct phases.

These are:

  • Pre-test Phase
  • In-test Phase
  • Post-test Phase


Pre-test Phase

During this first phase, the examiner will:

  • inform the examinee of the specific issue that is being investigated;
  • advise the examinee of his or her constitutional rights, of their right to an attorney and of the voluntary action of submitting to a polygraph examination;
  • complete the necessary documentation;
  • provide the examinee with a detailed explanation of the polygraph instrumentation with its components and how these work;
  • answer any questions that the examinee may have;
  • obtain the examinee's version of the facts regarding the specific issue under investigation;
  • formulate and review with the examinee all the questions that will be asked of him or her during the polygraph examination.

Before moving on to the in-test phase, the examiner will fasten various painless components to and around the examinee's body, thereby connecting him or her to the polygraph instrument. These components are equipped with sensors that serve to collect, measure and record, onto polygraph charts, the examinee's physiological data obtained from three major systems in the body, as he or she answers the set of previously formulated and reviewed questions during the course of the polygraph examination.


  • a blood pressure cuff that is secured around the examinee's upper arm and centered over the brachial artery for the purpose of obtaining a continuous tracing of his or her cardiovascular activity (i.e., heart rate, blood pressure, blood volume);
  • two convoluted rubber tubes — called "pneumographs" — that are fastened around the examinee's chest and abdominal area for the purpose of obtaining a continuous tracing of his or her respiratory activity (i.e., breathing pattern);
  • two protruding electrodes each with an insulated seating — called "galvanometers" — that are attached to two of the examinee's fingers for the purpose of obtaining a continuous tracing of his or her electrodermal activity (i.e., sweat gland activity).

Next, the examiner will administer a functionality or calibration test of the polygraph instrumentation. This is done to ensure that the polygraph is in good working order at the time of the examination and to demonstrate to the examinee that he or she is suited to being tested using the polygraph technique.


In-test Phase (Chart-collection Phase)

The polygraph examination takes place during this phase.

Once the examination is underway, the examiner will administer a minimum number of three separate tests each lasting approximately 5 minutes — and a maximum number of six tests — wherein the examinee's physiological data will be continuously collected, measured and recorded, onto polygraph charts, as he or she answers the set of questions that were formulated and reviewed during the pre-test phase.

The examinee will have a two-minute relaxation period between each test.

Upon completion of the in-test phase, the examiner will analyze, interpret and evaluate the examinee's physiological data collected during the polygraph examination, after which the examiner will form one of the following professional opinions:

  • NDI - No Deception indicated

    The subject is telling the truth.

  • DI - Deception Indicated

    The subject is not telling the truth.

  • INC - Inconclusive

    The evaluation of the physiological data is inconclusive.


Post-test Phase

During this last phase, the examiner will give the examinee the result of the polygraph examination. If the physiological data recorded on the charts shows reactions on the part of the examinee to the relevant questions that were asked, he or she will be given the opportunity to explain these reactions.

Once the post-test phase is finished, the examiner will provide the client with a verbal report of the polygraph examination and its result. This will be followed, in a timely manner, by a written report containing a factual account of all the information developed during the polygraph procedure, as well as the examiner's professional opinion of the examination results based on the analysis, interpretation and evaluation of the polygraph data.


Systems and Methodology

Polygraph examinations are administered using either the Limestone Polygraph Professional Suite from Limestone Technologies Inc. or the Lafayette LX4000 from the Lafayette Instrument Company, both of which are state-of-the-art systems of computerized polygraph technology.

Galianos Polygraphe Expert adheres to a set of Standards of Practice and a Code of Ethics required by the Canadian Association of Police Polygraphists and the American Polygraph Association.

The Zone Comparison Technique is used for all polygraph examinations. 

The polygraph charts are evaluated using a numerical evaluation scoring system that was approved by the Canadian Association of Police Polygraphists and the American Polygraph Association.

Computerized polygraph charts are further evaluated using a software program called PolyScore, a sophisticated and highly reliable mathematical algorithm-based chart-scoring system that was designed and developed by statisticians at the Johns Hopkins University Applied Physics Laboratory, in Maryland.


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