Cops are crunching data to stop baddies before they strike

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In his story "The
could arrest would-be perps before they struck. We don't have cops armed with
precogs quite yet, but lawenforcement agencies throughoutthe coultry are adopt-
statistical approachto policing that can help predict when andwhere crimes
are likelyto occur. Pulling together burgeoning public data sets on everything from
school schedules to home foreclosures and correlating themwith crime stats, analysts can spot surprising patterns that help departments anticipate problems and
identifii emerging hot spots. Here's how four cities are using predictive policing
BEISER
to get a jump on the bad guys.
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LOS ANGELES
MEMPHIS
Lock your
Minority Report," Philip K. Dick envisioned a future when police
doors-it's spring break!
Car
Unlversity of Memphis Eriminologists and local police mashed up
business-analytics software with geotagged data to create a tool
they've dubbed Blue Crush. lt compiles crime reports and layers in
variables like weather, iighting conditions, and proximity to concert
venues, along with reporting from PDA-equipped beat cops, to find
connections. For instance, the system noticed that colleges' springbreak week reliablV spawns a rash of burglaries.
thefts spread like chemical reactions.
According to UCLA anthropologist Jeffrey Brantingham, analysts
can use "reaction-diff usion" models-typically deployed to study
molecular interactions and bee swarms-to explain the incidence of
opportunistic crimes like burglary and cartheft. By modeling thieves
and victims as simple particles in Brownian motion, his system can
predict actual crime patterns and suggest preventive strategies.
The LAPD uses it to figure out where to deploy extra patrols.
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MINNEAPOLIS
ARLINGTON, TEXAS
Building code violations
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Need to find a gang banger? Gheck the library.
increased burglaries.
special Crime Analysis Unit identif ies locations where gun crimes
have been reported-notjust robberies and shootings but also gun
Cops in this Dallas suburb mapped residential break-ins against
building code violations and fDund that crime skyrockets around
dilapidated structures. For every "unit" of physical decay-even
A
cosmetie things like broken windows, graff iti, and abandoned
on
cars-there were six burglaries. Police
have begun working with other city
agencies to clean up aTeas that the
maps f lag as "f ragile neighborhoods."
thefts and illicit possession-then factors in geographic details
things like bus routes and proximity to parks, liquor stores, and
public libraries. (Yes, libraries: Turns out that gang bangers frequent them for f ree lnternet access.) Combining that with seasonal
data enables them to predict, for instance, when certain parks will
become trigger points for gun violence.
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