The Methods Used in Crime Prevention and Investigations

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We are living in the 21st Century where the society is in a unique position in relation to progress and speed with regards to scientific advancement and various emerging technologies. The present world is brimming with complexities, development, and fast change. At this rate prediction is that society will encounter 100 years’ worth of advancement and advancement inside the initial 25 years of this century. Advancements in technologies, for example, genomics, neuroscience, nanotechnology, information innovation, correspondence innovation, and surveillance technology will make raise new issues and predicament for society everywhere and for the courts as well.

However, with this enormously growing knowledge comes incredible obligation – obligation to guarantee that our ground breaking, forward-moving viewpoint, energy, and desire do not cloud our judgment and undermine our obligation to keep up the fairness of the criminal justice system. As the litigation system becomes more and more complicated, there arises the need for more expert opinion and input. The combination of scientific advancement combined with the law’s requirement for evermore logical and scientific advice creates a tension that cannot be overlooked. But the desire of the judicial system to get the correct answers should pull the use of science in to the court before it is fully ready. The crossing point and tension between different scientific and technological orders and the lawful framework are generally acknowledged. An expanding number of discoveries and developments are thought to have forensic applications, an idea reflected in the number of items and resources that are promoted towards the criminal justice system. However discoveries and innovations cannot go directly from the research centre to the court. Before a technology, technique, or hypothesis is proper for legal use, it must be approved.

As we are now dealing with a modern society based on scientific advancements and information technology, the criminal also tends to be shrewd and clever. The technical knowledge of a person has grown rapidly in these last few years. Criminals are now being more aware of the latest developments in the system. They themselves have become more scientific and modern. The modus operandi used by them is such that they leave no trace or evidence behind. This is where the scientific methods of investigation through the use of forensics become very important in criminal investigation. Of these methods, Brainmapping, Polygraph Test and Narco Analysis are the most popular which have been called into action by various investigative agencies around the world. The question arises as to whether these three scientific methods are legal and whether it is against Article 20(3) of the Indian Constitution; take a look at the important judgments given by the courts and their implications.

Scientific Tests for Criminal Investigation

Brainmapping or P-300 test: Brainmapping is a valuable tool for investigation of crimes. Brain Mapping is also known as Late Positive Complex or P3 or P300. It is a component of averaged brain potentials. In this test no questions are asked from the accused. He is made to sit in evoked potential recording machine and is shown objects relating to crime scene or is made to hear sounds pertaining to crime site. The sensors from his head pick the event related potentials in the form of Brain Mapping only if the person has been at the site of crime. The accuracy of Brain Mapping is almost 100 per cent.

Brain Mapping is a response of the brain to a stimulus which is shown to the subject. In 1965, scientists were working on the research of Event Related Potentials and it was discovered by Sutton and his colleagues. It is very robust Event Related Potential. As soon as it recognizes the stimuli it sends the reaction within 300 milliseconds of seeing the stimuli. If the person is attentive to the stimuli its response would be the fastest. If more time is taken for making decision the more time is spent for the responses of P300. Its latency shows the amount taken by it in arriving at a decision.

When the brain recognizes a person or a sound, it produces a precise electric wave which is called P300. In this test sensors are attached to the head of the subject and the subject is seated before a computerized monitor. The sensors catch the electrical activity in the brain and record P300 wave, which is produced only if the subject has some correlation with the pictures shown to him and the sounds which he is made to hear. Brain fingerprinting device was invented by a U.S. scientist Dr. Lawrence A.

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Farwell in early 1970’s. He is former faculty of Oxford University. He is the Chief Scientist and President of the Human Brain Research Laboratory founded by him in 1991. According to him, centre of every activity is brain and it not only plans activities but orders for its extension. The “Truth Detector” is based on the functions of brain. Every event is stored in the brain and when the same or similar event is shown to person the brain responses and response is recorded through computer.

The familiarity reaction of brain towards the activity or events is recorded in MERMER (Memory and Encoding Related Multifaceted Electroenceptalographic response) apparatus. Measuring EEG (Electro Encephalograph) from several place of scalp a special head band equipped with electronic sensors, is attached to the scalp and the test is presented with a series of relevant and irrelevant words, pictures, signs, etc.and responses of the two different types of stimuli is measurable to know whether the relevant material is known to the brain or not. If the brain is confronted with the stimuli, which is already in its store it will emit P300 at the rate of 300 mili seconds. Since, those responses are recorded EEG signals no question has to be answered by the test. The apparatus works not on emotions but on Cognitive Brain responses.

Polygraph test: Polygraph is another important scientific tool of investigation. Polygraph is popularly known as lie detector and sometimes referred to as psycho-physiological detection. It is an instrument which measures and records physiological actions of human body as for instance blood-pressure of the subject, his pulse rate, respiratory system, skin conductivity while the subject is asked questions relating to the crime and he answers them. The polygraph tests measures all the natural changes caused by autonomic nervous system during questioning. The autonomic nervous system changes are beyond reasonable control of an individual and hence autonomic nervous system response changes transpire when the subject tries to tell a lie. Polygraph is a device that records simultaneously tracing of several different pulsations, as arterial and venous pulse waves, and the apex beat of heart.

According to Encyclopedia Britannica, “Lie Detector” is an instrument for recording physiological phenomena (including blood pressure, pulse rate and respiration) of a human subject as he or she answers questions asked by an operator. The polygraph is an instrument that records certain physiological changes in a person’s body going through the questions in an effort to get hold of the truth or deception.

In India, since 1974 more than 3000 polygraph tests have been conducted. Lawyers in general were not aware of this test. It was a tele-serial ‘Sach ka Samna’ that brought polygraph test in glare of public as the show also uses polygraph test on the participants. The polygraph works on the principle that change in a person’s perception or consciously held feelings produces a reaction in the form of physiological changes, e.g. in the pulse rate, blood pressure, respiration rate and the electrical resistance of the skin known as G.S.R. when a person is truthful, the body functions within, its normal patterns with no significant or consistent changes.

Narco Analysis: It is a kind of psychotherapy which is conducted on a person by inducing by bringing that individual into semi-sleep with the help of scientific drugs. Human beings have the tendency of speaking lies from the time immemorial. A person is able to lie by using his mind’s eye. In this test, the subject’s self-consciousness is allowed to sink down by making intrusion to his nervous system. In such a state an attempt is made to extract information in form of clues about the crime as under the influence of drugs it becomes extremely difficult for the subject to lie.

It is believed that if a person’s way of thinking can be restrained without any affect on his memory. He can speak freely without any manipulations under the influence of drugs. Some drugs have been found to create this ‘twilight state” in some persons and with the use of these drugs investigating agencies try to arrive at the truth. Narco-analysis is a form of psychotherapy and an effective aid to scientific interrogation. It is a process whereby a subject is put to sleep, or into a state of half consciousness by means of dosage of scientific drugs and then interrogated while in a reverie.

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