Page 50 - BBC Focus - August 2017

PREDIC TIVE

POLICING these locations?” he says.

“Instead, we should be asking
why this location has a persistent
crime problem, and what we can
do to keep it from happening.”
CAN WE PREDICT CRIMES BEFORE THEY HAPPEN? Eck would prefer it if the police
encouraged owners of
businesses and other properties
highlighted as crime hotspots to
step in and make changes, such
It’s 4:30am on a Friday morning on those that help to predict as shops with high shoplifting
in August and there’s a heavy when and where the next rates repositioning displays.
police presence in a quiet London earthquake aftershock will be, or Critics have raised other concerns
suburb. It’s a respectable, leafy how a disease will spread. too, such as the possibility of
area and right now, nothing is These algorithms generate crimes simply shifting to other
happening. In fact, it’s been quiet information that police officers locations when problem areas
for the past few days. But the can act on, and it seems to work. are targeted by the police.
officers are on high alert. They’ve In tests, their predictive powers But predictive policing is
been sent at the say-so of a appear to outperform the more becoming more and more
computer that’s calculated, on traditional techniques used by widespread, and it could be
the basis of the data fed into it, crime analysts. Their successes about to change radically. Earlier
that a wave of break-ins is highly have led to predictive policing this year, a bunch of
likely within the next 24 hours. In being adopted by several US mathematicians led by Prof Mark
other words, they’re policing police departments, such as Girolami at Imperial College
crimes that they think will California and Arizona, as well as London were awarded £3m from
happen, rather than ones that Kent Police in the UK. the government to take
have happened. This is predictive But not everyone’s convinced predictive policing to the next
policing. And it’s about to get about predictive policing – or level. Whereas today’s tools just
much, much more sophisticated. how it’s implemented at least. rely on crime data – such as the
The idea of predicting where Among them is criminologist Prof locations, dates and times of
crimes will take place isn’t new. John Eck at the University of incidents – Girolami and his team
For decades now, police forces in Cincinnati. His problem isn’t so will be working on how to
the UK and US have been creating much with the predictive policing integrate the likes of Twitter
‘hotspot’ maps that identify the software itself, but the idea of feeds, newspaper reports and
areas where most incidents are sending out large numbers of socioeconomic data to sharpen
taking place, and then sending staff to patrol problems the predictions. Text documents
more police officers to those highlighted by the algorithms. will be converted, or ‘coded’, into
areas. Predictive policing takes “Why would you want to keep numerical representations, with
this to the next level, crunching sending large amounts of counts of words and phrases
big data using algorithms based expensive public servants to – such as descriptions of assaults
or break-ins – to highlight
geographical areas of concern.
Staff from the “All of these streams of
University of
California information will be coded and
demonstrate integrated using our ‘secret
predictive sauce’,” says Girolami, referring to
policing with
Los Angeles the complex maths that will draw
police all of this disparate data together.
What’s more, this new
predictive tool aims to work out
the extent to which crime will be PHOTO: SHUTTERSTOCK ILLUSTRATION: VLADO KRIZAN
displaced to a neighbouring area
when the number of police in the
original area suddenly shoots up.
“Our models will be able to
propagate what would happen,”
says Girolami.

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