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Advancement of forensic science in criminal investigation
Introduction: Crime has been a part of human society from the time immemorial. The need of laws and various kinds of legislation was felt when crime started threatening the very existence of the human society. The laws and legislation of various kinds are therefore weapons of human society to fight against the evil named crime.
Crime is both a social as well as an economic phenomenon, which distresses the whole human society. With the growth and development of society the nature of the crime has been also changing and diversifying. Today, guardians of law heavily depend of various technologies and advancement of science to help them in their fight against crime. There has been various advancement in forensic science that has specially been welcomed in criminal investigation. Some of such advancements are discussed below in brief while efforts have been done to study DNA profiling in details. However, any discrepancies that may have crept in are regretted.
Polygraph or lie detector test:
The first attempt to develop a scientific instrument to detect truth or deception was made as early as 1895 by Lombroso. It was basically designed to record blood pressure and changes in pulse rate. Later Larsen and Keeler designed instrument which was further developed by John Reid in 1947.
The principle behind the mechanism of this instrument is that, a change takes place in a person who consciously holds his feelings, which manifest into change in blood pressure, respiration or electro dermal response.
Such test is conducted on the basis of assumption that there is an interaction between mind and body and is conducted by various components or the sensors of the polygraph machine, which are attached to the body of the suspected persons body that is being interrogated. The machine records details like blood pressure, pulse rate, respiration and muscle movement etc. This test is conducted at three...