7 Finding and identifying criminals: early forensic science

Finding and identifying criminals is at the core of police work. During the nineteenth-century, before widespread identity documents, police found it hard to tell whether someone they had in custody was who they said they were. One early solution was the ‘anthropometry’ system, developed in France by Alphonse Bertillon in 1879. This involved combining photographs with detailed bodily measurements of those arrested, to produce card indexes of criminals which could be searched if people were re-arrested. While used by some forces in the UK, this was soon superseded by the fingerprint system.

Figure 11: A Metropolitan Police Detective uses the fingerprint library at New Scotland Yard (1946) [Description: A black and white photograph showing a detective in a suit leaning over a desk examining an entry in a large register of fingerprints with a magnifying glass. Behind the desk are shelves stacked with further registers or indexes] Source: https://www.gettyimages.co.uk/detail/news-photo/metropolitan-police-detective-examines-fingerprint-records-news-photo/1660849873?adppopup=true

Fingerprints had been known as a unique quirk of individuals from the end of the eighteenth century, but it was not until 1880 that Henry Faulds, a Scottish surgeon, considered their potential usefulness for identification and proposed recording them with printing ink. He offered the concept to the Metropolitan Police in 1886 but it was dismissed. In 1901, however, Sir Edward Henry, a former Inspector-General of Police in India and the author of Classification and Uses of Fingerprints, was appointed as Head of CID at the Metropolitan Police. He established the Metropolitan Police Fingerprint Bureau the same year.

In the early twentieth century, ‘dactyloscopy’, as fingerprint identification was then known, was seen to represent ‘the modern, scientific approach to criminal identification ... the mark of cosmopolitan police organization’ (Cauchi and Knepper, 2009). Initially, exemplar fingerprints were taken from suspects and criminals, to enable their reidentification if re-arrested. Then, in the 1930s, the use of latent fingerprints (left behind at crime scenes) was pioneered, broadening their use by the police. The fingerprint library at New Scotland Yard contained over 250,000 fingerprints by the 1930s.

Many other forensic techniques were also developed during the 1930s, which has been seen as a period when ‘science in ... policing began to come of age’ (Adam, 2016, p. 119). Following reports by the ‘Advisory Committee on the Scientific Investigation of Crime’ and the ‘Departmental Committee on Detective Work’, a new Metropolitan Police Laboratory was opened in 1935.

This led eventually to the establishment of regional forensic science laboratories trialling a host of techniques involving microscopy, ballistics and chemical analysis of crime scene residues. While there were continual tensions between those advocating that ‘real’ policing was only conducted by trained police officers at crime scenes and those who favoured a more ‘continental’, lab-based approach (Burney and Pemberton, 2016), new ‘scientific aids’ were gradually introduced into daily police use.