Is polygraph a reliable lie detector ?

Polygraphs, also called lie detector are utilized to catch individuals in the demonstration of lying by observing their physiological action.

Is polygraph a reliable lie detector ?Creating such an investigation instrument was proposed by August Voltmeter in 1921 who was Berkeley’s Chief Police Officer. However, rather than taking a shot at this himself, he passed on these guidance to one of his officials, John Larson.

The absolute first polygraph that he made was utilized to record heart and breathing rates. Polygraph examiners are prepared particularly so they have a comprehension of the components that administer their analysis. The analysis of this test anyway isn’t as objective as one may see it to be. It is exposed to the analyst’s very own elucidation which may feature the component of biases.

Before applying the test, it is fundamental that the examiner decides his subject’s stress instead of expecting that they’re equivalent to every other person. The legitimacy of the use of a polygraph to identify deception has been somewhat controversial from a long time. Polygraph examinations have been widely used both within and outside Psychology to prove victims guilty of their crimes and exculpate innocent suspects.

Private firms have increased the used of polygraph in efforts to reduce employee theft, likewise the government has also increased their use to protect national security. Despite their increasingly intense use, there are loads of questions being raised on their accuracy, and it is not easy to solve the contradictory claims.

From the most of the discussions done, two major problems of testing of polygraph are, one it is considered as the monolithic method. And second the expertise of the polygraph , rather than the testing situation, is emphasized. Both are them are the wrong imitations. A polygraph is an examination form of testing that is psychological and consists of disparate investigative techniques.

Rudimentary psychological changes that includes breathing rate, heart rate are observed through a set of structured questions. And the way respondent‘s automatic arousal in result of these questions changes, helps in assessing the honesty and deception of the subject.

Shockingly, in light of the fact that there is no exceptional physiological reaction to deception interpretation of arousal, indeed, a complex clinical undertaking. Various procedures have been created to structure questions posed in a polygraph examination. The decision of which technique to utilize relies upon the idea of the test circumstance.

Most significant, distinctive inquiry methodology are utilized for “specific incidence” investigations and showing circumstances. In particular occurrence test, a suspicious is examined concerning particular facts of a wrongdoing; in the process of screening, apparently legit people are posed expansive questions about their previous conduct.

Varieties in technique are additionally identified with the examiner training, however such contrasts normally influence the manner by which a technique is utilized instead of the decision of using a particular technique. Portrayed underneath are three noteworthy kinds of question procedure utilized in polygraph tests: the relevant/irrelevant technique (R/I), the control question test , and conceal information tests (CIT).

Likewise portrayed is the configuration of run of the typical polygraph examinations. As will be appeared, mental states of a test, alongside the sort of question technique, importantly affect the rationality of polygraph tests.
For the examination of polygraph, one is situated and is snared to a lie detector and posed a progression of inquiries which may either be relevant or control based.

Important type of questions are clearly those that are identified with the current case. Assume that charges have been squeezed against you for molesting a 12 year old girl. You’ll most likely be posed inquiries like “Do you know who Natasha is?” or “Have you attacked her?” You’ll likewise be required to respond questions in such a manner that offer somewhat more profundity than the ones expressed above for example;

” Did you head toward her home to do the wrongdoing?” or “Did you contact her?”. Control questions then again are considerate in nature and furthermore encourage the inspector in deciding his subject’s individual stress range. One is required to respond to these questions, for example, “Have you had your morning meal?” or “Is it raining outside?”

When you give the answers, any changes recorded in the blood pressure or respiratory, cardiovascular activity would be observed. If the reaction is not being noted when you have been asked a controlled question but got notified when you have been asked any relevant question, then you will concluded on telling a lie and vice versa.

A tip that would help you if in any case you fail to find out the cheating code. You need to learn how to remain calm and composed when a relevant question has been asked from you and display a reaction when a control question has been asked by you. You can do this by thinking about anything that makes you petrified or fuming.

As elucidated above, one can easily manipulate this test with the help of self-assurance as well as a little bit of practice. Even, there numerous other factors from which one can lead to false judgments. The stress that a person takes when he knows he is being examined is considered enough for activating a fight and flight response of a person.

So if we make a conclusion, that polygraph has that much ability to detect lies as any normal person or the judge has. Polygraph are only considered helpful if the person being investigated truly believes in them and speak out the truth instantly. But one should be careful and avoid risks as any judgement made by using this instrument could result in life changing events for a person.

Authors: Amna Aslam , Wajeeha Nadeem

Psychology department of Kinnaird College for Women, Lahore