152 Before the Bobbies
There was (and is) a tension between prevention and detection not often
acknowledged; Jeremy Bentham and his disciple Edwin Chadwick included
detection as one of several characteristics of preventive policing. Chadwick
argued that one of the principles of preventive policing was 'that every
arrangement which diminishes the chances of the personal escape of the
depredator, is so much gained in diminution of the motive to commit
crime'.^16 Some, like Patrick Colquhoun and Robert Peel, emphasized pre-
vention as preferable to detection but none saw any conflict between these
two goals and most assumed one body of men could do both. The preamble
to the Metropolitan Police Act stated that the statute was needed because
the night wat~h had been found 'inadequate to the Prevention and Detection
of Crime' and the new police were expected to prevent and detect offences.^17
Watch authorities had struggled with this dual responsibility as well. Th have
a watchman calling out the hours did not enhance the ability of that man to
detect a thief in the act. Yet calling the hours and having regular beats,
prevented crime while the watchman was in that particular street to observe
any suspicious activity. As we have seen, the night watch was primarily
intended to be a preventive force.
Detecting criminals in the act or solving a crime already committed
requires different skills and tactics. This was recognized in practice: the
Bow Street Runners continued as plain-clothes officers until their separate
existence was ended in 1839. Within a few years, however, Rowan and
Mayne reluctantly acknowledged the need for a force of plain-clothes offi-
cers and formally organized a Detective Division of eight men in 1842.^18
Thus the dichotomy that had developed in the eighteenth century was
perpetuated. Officially, 'the Metropolitan Police' carried out both functions,
but the same men did not prevent and detect crime at the same time.^19 The
two functions without doubt are related but they are essentially different and
were achieved by very different methods.
This duality appeared in the initial operation of the Metropolitan Police.
Constables were uniformed and walked regular beats but they patrolled
silently, enhancing their detective role. The first Metropolitan Police officers
wore dark blue, long-tailed coats with matchinJ or, in summer, white trou-
sers and dark top hats, with reinforced crowns. The intention was in part to
differentiate policemen from soldiers but it also made them less conspicuous
and increased the chances that they might catch some burglar in the act.
Although they were in uniform, their dress did not enable Metropolitan
policemen to be distinguished at a distance or in dim light from the male
citizenry at the time.
Prevention is enhanced by impartial surveillance. However, apprehension
of suspects is more likely if policemen are familiar with neighbourhoods and
know who is and is not a likely suspect. Just how familiar should the police
be with the community? Parish forces grappled with the issue, using rotating