At LAPD, Predicting Crimes Before They Happen Using years of crime statistics, the department's computer churns out maps with small highlighted areas where it predicts a crime will occur. Police hope that the technique helps reduce crime, but there are concerns over how the data will be used.
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At LAPD, Predicting Crimes Before They Happen

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At LAPD, Predicting Crimes Before They Happen

At LAPD, Predicting Crimes Before They Happen

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This is WEEKEND EDITION from NPR News. I'm Scott Simon. We begin this hour with the latest advances in law enforcement. In these times of tight budgets, police departments across the country are looking for new ways to save money, and one way is to try and predict where crime will strike before it happens. It's called predictive policing. In Los Angeles, the strategy took off under then Chief William Bratton, and we'll hear from Chief Bratton in just a few minutes. But first, as NPR's Carrie Kahn reports, L.A. cops this month are rolling out new technology they say will predict crime like never before.

CARRIE KAHN, BYLINE: Captain Sean Malinowski does his crime-fighting in front of a computer screen.

CAPTAIN SEAN MALINOWSKI: That looks like assault with a deadly weapon with a vehicle.

KAHN: He's in the LAPD's RACER Division. It's located in a new crime data and analysis center just built in downtown Los Angeles. Malinowski is tracking two crimes that just occurred.

MALINOWSKI: And they're within, what, a few blocks of each other here in the South L.A.

KAHN: Patrol cars are already on the scene. Malinowski says this facility is state of the art in real-time policing. Now he wants the force to be the best in predicting where criminals will strike. For the past several years, he's been working with a team of researchers from UCLA. This month, they are finally rolling out a new computer program to do just that. Using years of crime stats, the computer churns out maps with small highlighted areas where it predicts a crime will occur.


KAHN: Lieutenant Scott Harrelson drives to one of the areas, or boxes.

LIEUTENANT SCOTT HARRELSON: They're headed to Osborne and Glenoaks.

KAHN: So it's a pretty small area you're going to, right?

HARRELSON: Approximately 500 feet by 500 feet is my understanding. A city block, so to speak.

KAHN: When not on radio calls, cops in this northern patrol division of Los Angeles spend as much time as they can inside a box. Harrelson says officers won't do anything different there then they did before.

HARRELSON: It just means while they are in that box and in that area, they are going to be paying a lot more attention.

KAHN: So far, it seems to be working. That's what Captain Malinowski tells his officers at their morning muster.

MALINOWSKI: Let me tell you, we have week one results now that we looked at during the first week of this test - if you want to call it that. We had 30 of those crimes in the division reported.

KAHN: Thirty property crimes, burglaries and car thefts. Malinowksi says that's a 50 percent decrease compared to the same week last year. He's not yet declaring predictive policing a success. He'll wait six months to do a complete analysis. But in Santa Cruz, California, the police department has using the UCLA program since July with similar results. UCLA anthropologist Jeff Brantingham says he's not surprised. Human behavior, especially when in search of resources, follows very predictable patterns. For his Ph.D., Brantingham studied foraging strategies of ancient hunter and gatherers in Mongolia.

JEFF BRANTINGHAM: It's surprising how similar the problems are; how it is that ancient hunter-gatherers found gazelles on the Mongolian steppes is very similar to how it is that offenders find a car to steal.

KAHN: And he says crime, especially property crime, happens in predictable waves.

BRANTINGHAM: If your house is broken into, the chance that it is going to be broken into again goes way up, and in fact, your - the chance that your neighbors' houses is going to be broken into goes way up.

KAHN: That's because crooks now know the area and go back to where they had success. Brantingham says these crime waves show up in patterns similar to the aftershocks of an earthquake. While the science is impressive, Loyola law professor Stan Goldman says he worries how the data will be used. Despite police assurances, he says cops could use it as reasonable doubt to stop and search innocent suspects who happen to be in the highlighted neighborhoods.

STAN GOLDMAN: It may very well end up reducing crime to a certain degree. The question is at what cost, at what price?

KAHN: L.A. cops say the computer will never replace good policing practices, and that's it's a much-needed tool, especially as budgets are cut and police forces are stretched thin. Carrie Kahn, NPR News.

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