A handy detection method at tips of imperial fingers

Colonial rule in India made its mark on the British as well as on the Indians over whom they ruled. In the case of fingerprinting, this was literally so, for, as Chandak Sengoopta demonstrates, the origins of this now standard forensic technique lay not in the furtive and foggy London of Sherlock Holmes but in the up-country Bengal of a young British magistrate. In 1858, anxious to secure a binding contract with an Indian businessman, the local civil servant, William Herschel, asked for an inked impression of his hand on an agreement to supply road metal.

But the idea of using handprints, or more economically fingerprints, as indelible signatures languished for several decades. In India, as in France, the police turned instead to the elaborate anthropometric system devised by Alphonse Bertillon, which sought to register and classify individuals on the basis of a series of anatomical measurements and identifying features, including eye colour and even ear shape, painstakingly recorded on hundreds of special cards.

Herschel's pioneering idea was eventually taken up in Britain by Francis Galton, who published a book on fingerprints in 1892, and in India by Edward Henry, inspector-general of the Bengal Police, who developed and persuaded the local government to accept a practical system for registering and classifying fingerprints. It was thus in India that fingerprinting was first used forensically to secure a conviction, in a Bengal murder trial in 1897. Having proved effective in its colonial laboratory, the system was soon adopted in Britain. In 1902 a Home Office committee approved the use of fingerprinting to identify criminals, and Henry, appointed commissioner of the Metropolitan Police a year later, set up a fingerprint branch in London and so helped install the fingerprint system at the heart of the empire.

Contrary to the common - if increasingly contested - presumption that all innovation flowed outwards from the imperial metropolis to the margins of empire, Sengoopta persuasively shows how in this case (and by inference others) Britain was the beneficiary of practices that had their origins in India, or at least how innovative policing relied on a continuing dialogue and exchange of personnel between Britain and its colonies.

More specifically, fingerprinting is seen to have arisen from a compelling need in post-Mutiny India for a more reliable knowledge of Britain's imperial subjects. Fond though they were of collectivising Indians into "castesand tribes", and thus recording supposedly shared moral and physical attributes, the British found individual identities more difficult to pin down. In a society where so many people were illiterate and where criminality seemed ingrained, they felt themselves to be deceived by "slippery facts", confronted with duplicitous Indians whose testimony could never be relied on in court unless backed by material and incontrovertible evidence such as that provided by fingerprints. Even though fingerprints proved not to be race-specific, the fact that fingerprinting first emerged in India was thus no coincidence but rather indicative of a deep-seated imperial distrust and a constant slippage between the colonised and the criminalised.

A readable, well-illustrated book, and in many respects a fascinating and informative one (with even a technical appendix to guide the reader through the arcane architecture of arches, loops and whorls), it is a pity that in the search for a popular market Sengoopta and his publisher have seemingly spurned a more scholarly readership by omitting all footnotes and specific references to sources. A guide to further reading is poor recompense, diminishing the usefulness of this otherwise valuable insight into the inner workings of British India and the nature of colonial-metropolitan exchanges.

David Arnold is professor of South Asian history, School of Oriental and African Studies, London.