General Uses

A polygraph examination can be used as a technical aid during the course of an investigation. It can help verify the statements of the complainants, establish the credibility of the witnesses, or assess the suspect’s honesty.

The term “polygraph examination” refers to the entire questioning process, as well as the choice of one chart from a series of questions, or the entire test’s charts and question sheets. The examination is conducted in the following stages: preliminary preparation, conduct of pre-test interview with the persons to be examined, conduct of the actual instrumental test, and post-test interrogation.

Here are some useful related terms:

• polygraph chart also known as polygrams, a permanent chart or graph that records all emotional patterns based on a series of questions
• polygraphist also called a polygraph examiner or forensic psychophysiologist, the person who conducts the actual polygraph test or examination
• subject anyone who is undergoing a polygraph examination or test, regardless of whether they are the victim, witness, or suspect in the crime

Importance of Lie Detection

As already mentioned in the previous section, polygraph examinations can be used beyond criminal investigations. It can be used in any type of investigation involving interview and interrogation. These are why the polygraph examination is important in the field of investigation:

1. It enables faster and more accurate detection of deception
2. It has been shown to have a decided psychological effect in inducing confession from a guilty subject
3. It helps innocent people be spared from fear, embarrassment, and inconvenience
4. It minimizes the use of THIRD DEGREE practices particularly upon innocent subjects
5. It aids investigators in getting all the facts regarding the offense under investigation

Principal Uses

Just like all other allied sciences under Criminalistics, polygraphy has specific primary purposes for which it is used:

1. Aid in investigating criminal incidents and issues
2. Speed up the process of investigation
3. Eliminate innocent suspects
4. Screen job applicants
5. Check the honesty and/or loyalty of members of specific groups