Polygraph Examination

Initial Interview with the investigator 👤

Pre-Test Interview 👥

Instrumentation ❓

Post-Test

Receive letter request in quadruple copies

Review Facts of the Case with the investigator

Get sworn statements of complainant, suspects and witnesses

Review case folders including investigation reports, crime scene sketch, photographic evidences etc.

Get the personal information of the subject

Brief the subject with the objective of the test

Aquaint the subject with the polygraph machine

Review all the questions to be asked during the actual test

Determine the suitability of the subject to the test

Psychological and physical evaluation conducted

Physical, Medical and Psychological Evaluation

Inform his rights under the constitution and existing confession laws

Warn the subject about the legal consequence of lying

Subject must seat comfortably

Subject is instructed to relax

Subject will be asked questions answerable by yes of no

Qhestions are combination of irrelevant, relevant and sometimes control questions

Attach the pneumograph sensors

Place the cardiosphygmograph sensors

poly machine liar

Central-Polygraph-Service-How-Polygraph-Works

Attach the finger electrodes to the other hand (index and ring fingers

Get baseline recordings as you ask irrelevant questions

Once the baseline tracings are stable ask relevant questions and comparison questions in an alternate manner

Adapt a polygraph questioning format suitable to the test e.g. General Question Test (GQT), Control Question Test (CQT), Peak of Tension Test (POT), Zone Comparison Test (ZCT) etc.

Consider suggested stimulus markings and identifiers for later interpretation and analysis

If the examiner finds No Significant Response as seen on the Chart, release the subject cordially and thank them for their cooperation

In cases where their is a strong indication of deception as shown on the chart, work on getting a confession by applying the Reid Technique of Interrogation

If indications of deception are detected on responses to control questions, conduct probing technique to verify hidden informations concealed by the subject; work on possible admission by the subject

In cases of confession is made, be sure to reduce it in writing in the presence of the subject's lawyer; confession must be voluntary and signed by the subject

Obtain consent

Miranda warning

To condition the subject for the test

Must have eaten his/her meal prior the test

In case of female subject, must not be pregnant at the time of the test

Have not smoked 2 hours prior to the test

Not experiencing any pain from illness or disease

Subject must have enough sleep