Lifting fingerprints to soon get easier for Delhi Police

Delhi Police will soon acquire Reflected Ultra Violet Imaging System (RUVIS) which will help policemen capture fingerprints from surfaces long after an incident of crime has occurred.

“Under the present powder and brush method used by the investigators, chance prints (prints of the foot, palm, fingers, toes and shoes which a culprit leaves accidently and are not visible by eyes) are required to be captured as soon as possible following an incident to negate the impact of environment on the prints,” said a fingerprint expert.

Fingerprints are extremely fragile and whatever left of them can dry out very fast. Unlike the powder and brush technique which depends upon the moisture content to extract prints, through Ruvis one can extract even the organic matter which remains on the surface once the moisture is gone.

Presently used in the Western countries, Ruvis uses ultraviolet light to capture the prints.

“Heat produces reaction which develops moisture and eventually helps create fingerprints on a surface. In winters, due to the lack of heat and moisture, capturing chance prints is very difficult. But with Ruvis, we can easily capture the prints as it sends ultraviolet light on the surface and captures the residue once the water dries up,” said the expert.

With the powder and brush method, impressions are sometimes not clear due to several factors, including the wrong use of brush by policemen. “Even a slight mistake in using the brush to capture prints can ruin the fingerprints altogether. With Ruvis, we don’t have to bother about such things,” the expert added.

Apart from Ruvis, Delhi Police are also thinking of purchasing Thermal Fingerprint Developer (TFD-2) device which is meant to extract fingerprints from large quantities of paper documents.

“In crimes where large volumes of office paper must be examined, the TFD-2 dramatically reduces search time and manpower requirement,” said a senior Delhi Police officer.

“In TFD-2, an evidence is placed on the motor-driven conveyor and passed through the TFD-2 optimised-heating element. The action of briefly raising the temperature of the document causes a chemical reaction producing a fluorescent byproduct which is visible under intense visible light and the fingerprints show up,” he added. Costing around Rs 7-8 lakh, the TFD-2 is mainly meant to investigate white-collar crime.