Investigators say long delay may affect lie-detector test

Says an officer investigating the case: 8220;We are sure we will establish that one or more persons are lying, or holding back information related to Shivani8217;s murder. Ultimately, though, we have to have return to basic investigation to establish who killed her.8221; He adds: 8220;Of course, the results of the lie-detector test will not be admissible in a court of law. The report is merely to facilitate investigations.8221;

Ravi Kant Sharma, currently vigilance chief with Air India in Mumbai, is the only one among the four persons scheduled to be put through the test in the Shivani case to have seen a lie detector earlier. He has worked with the CBI for six years, then Interpol and then in the Prime Minister8217;s Office.

In Delhi, and several other states, a lie detector is a luxury for investigators. For example, the Delhi Police don8217;t have one and every time they require it, they have to borrow it from the CBI. And the CBI makes it available only two to three months after a request is made.

8220;When I was the Police Commissioner, I remember that it used to take us at least two months to get hold of a lie detector. A lie detector is a great help during investigations, especially when the police start questioning people soon after an incident. Everything is fresh then,8221; says T.R. Kakkar, now Director General, National Security Guards.

He adds: 8220;In a city like Delhi, where there is lot of crime, which even raises questions in the Parliament, a lie detector is very crucial to speed up investigations.

All about the lie detector
What then is a lie detector, now vital to investigations in the Shivani case? A cursory look, and you will pass it off as another of those equipment you see in a diagnostic laboratory. In fact, it is a combination of electronic gadgets, each of which is used to measure blood pressure levels, register heart beats and even take into account whether the person, who is being questioned, is perspiring beyond normal limits.

First, electrodes are fixed on the body of the person who is being questioned. Then some of the wires from these electrodes are connected to an electro-cardiograph, some to an electronic manometer and the rest to a current conduction meter.

The cardiograph registers heartbeats, the manometer records blood pressure levels and the current conduction meter shows the amount of current flowing through the body. 8220;If the person is perspiring heavily and, probably lying, more current will flow. Ditto with high BP levels and and irregular heart beats,8221; says Director, Central Forensic Science Laboratory CFSL, S.R. Singh.

Explains ex-Delhi Police chief Kakkar: 8220;Before we put a person to the lie detector test, we almost always know where he is lying. The lie detector test is meant to be a confirmation of these doubts. When we frame the questions, with the help of psychologists, we keep this in mind.8221;

Adds CFSL director Singh: 8220;Every time a question is asked, the time is noted. There are similar arrangements on the electronic equipment monitoring the questioned8217;s reactions.8221; Two, psychologists, specially selected for the job, then analyse the response to each question and match them with data from the lie detector recorded at the same time.

8220;If we have doubts somewhere, we repeat the questions. And the process goes on, sometimes for two to three days,8221; says an official with the Crime Branch, requesting anonymity. 8220;We don8217;t know how much the lie-detector will help in the Shivani case as a result of the delay in procuring the equipment. But I have personal experience in seeing people break down, months after an incident has taken place. The lie detector does catch people lying.8221;