HOW FINGER-PRINT EXPERTS WORK

Hokitika Guardian, 31 December 1927, Page 4

HOW FINGER-PRINT EXPERTS WORK

(By Hugh. Brady). Finger-prints play such an impellent part in crime detection to-day that one of the first- lessons of a police recruit deals with "tiie subject. Sir Edward Henry, a former Commissioner of ihe Metropolitan Bolieo, inaugurated the system in 1961. and there are now at Scotland A ard nearly half a million impressions of convicted men and women. Emm a remote age the use of a finger or thumb piint to establish the authenticity of a document has been adopted. Sir Edward, who had been Inspector-General of the Bengal Police, was an earnest student of the subject for manv years, and when lie was appointed to Scotland Yard lie devised •i.nd perfected the classification of the various characteristics of the. fingerprint for the identification of criminals. A staff of about fifteen men, undei a chief inspector, have brought the system to such perfection that when the linger impressions of any individual arc placed before them they can almost simultaneously produce the criminal record, if the persons is not a first offender. Every person detained for a crime at a, London police station is invited to lane his finger-prints taken, and a few hours later, when the person appears in court, the record is ready for the magistrate should the ease he dealt with .summarily. Two finger-print experts deal each morning with tin- overnight charges for all London. The suspect’s finger prints are photographed and shown on a screen side by side with the impressions at the bureau. To the expert the result is beyond dispute A similarity in finger impressions taken from different individuals would mean the breakdown of the whole system. The export reads ir finger-print with uncanny speed and accuracy. He writes down the markings, and the result resembles an algebraic sum. In a moment he produces the index-card if the suspect’s record is in the li:ilimit 1 ion collection. To the uninitiated it would seem impossible fo pick nut accurately one person’s record from half a million. But the markings on the fingers, when reduced to a formula, make the task easy.

There are eight main groups oi linger impressions, divided into arches. tented arches, loops sloping to the I .ft, loops sloping to the right, whoils, central pocket loops, and accidentals. The hand is engraved with furrows which form elevations called ridges, end when the linger tom-lies. n smooth surface a 1 ell-tale impression is left. Leaving a clear impression of his fingers is a, folly seldom committed by tin' old criminal, who works with gloved hands, A blurred impression may be of great value in helping id 11 1ilicatioli. hut only when a person is suspected of a crime and the police are able to

make comparison. Occasionally a criminal unintentionally leaves his finger-prints behind. Fom;! burglars Imve been captured anti convicted because they took off their glove.-, to write a saury note or to eat a meal at a burgled house. Fingerprints can lie easily developed from pa-per. glass, delph, spoons, knives, cr forks. Ask a friend to grip firmly a piece of white paper. Nothing will appear. Sprinkle the area touched with graphite or lamp black and the impressions stand out in bold relief.