Stop and search powers are better seen as an investigative tool rather than a crime deterrent, a new study concludes.
Ten years of data from The Metropolitan Police was examined to see if stop and search had a deterrent effect on crime in London.
The study, which was a collaborative piece of work between University of Manchester and University of Oxford, found that higher rates of stop and search were occasionally followed by slightly lower rates of crime.
However, the associations found were inconsistent and small in size, which provided limited evidence of stop and search having acted as a deterrent at a borough level.
Dr Paul Quinton, Evidence and Evaluation Advisor at the College of Policing, said: "As we know very little about the effectiveness of stop and search powers, which are often the subject of intense public scrutiny, we wanted to take the opportunity of adding to the evidence base by examining data that were readily available from the Metropolitan Police.
"Ours is the first UK study to find any sort of relationship between stop and search and crime. We found some, but fairly limited evidence of it having had a deterrent effect on crime at a borough level.
"Extremely large increases in stop and search - of a scale likely to be unacceptable to some communities - would only deliver modest reductions in crime. "However, it does not follow that stop and search is ineffective against crime and there are suggestions that the power probably has more of an impact locally."
Dr Quinton added the situation is improving as the arrest rate from stop and search is increasing.
"The arrest rate is now at its highest level since records began and this suggests that the police are taking a more targeted approach to stop and search," he said.
As stop and search is an investigative power, it may be better to see crime reduction as a useful by-product rather than its main aim. In this respect, arrest rates from stop and search have improved in recent years, rising nationally to 16 per cent in 2015/16. The Met arrest rate was 19 per cent for stop searches in 2015/16.
Last year the College of Policing, as the professional body for the police, published new training and guidance for officers on the use of stop and search.
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