Lie In Crime Investigation

Today, with the fast developing science and growing living standards of people, an increasing trend to urbanization and modern living; number of crimes are increasing day by day. Crime is defined as an abnormal deviation causing harm to other members of society (Paranjape, 2009). Statistics and surveys show an increasing trend in rate of crime (NCBI, 2012).

Science has made it easy to commit crimes but hard to detect it and even more difficult to prove it in court of law without which whole of the investigations and findings are null and void. In the lack of witnesses, the job of investigator is getting difficult day by day. This investigation becomes lot more easy if lie is detected in the crime. Lies are the basic and most important aspect

This term is made from two words “poly” and “graph”. “poly” means many and “graph” means writing. The term ‘polygraph’ literally means many bodily activity that are recorded. This equipment is used in lie detection situation based on an assumption that lying is accompanied by the changes in activity measured by different components of polygraph because of the learnt fact that lying is immoral during the childhood period from teachers and parents. (Maschke and

Most popular tests used are Relevant/Irrelevant test (RIT), Control Question Test (CQT), Directed Lie Test (DLT) and Guilty Knowledge Test(GKT).

2) Polygraph testing in employment and security screening

It is used by government agencies and security services during pre-employment and post-employment screening tests. These are done to identify those who are likely to engage in activities that can be dangerous to the agency or those who may have past criminal records. In some agencies they are used on periodic basis for working employees. They are also used for security screenings to identify security threats and risks to the state. FBI, CIA, DOE, DoDPI etc. use this technique at large and perform thousands of tests every year for pre-employment screening, periodic screening and security clearances. In India, it is not used for any such pre-employment or periodic screening.

3) Polygraph uses for clinical purposes i) to assist in establishing identity of an allegedly amnesic patient. ii) to diagnose genuine blood injury phobia while giving a blood