Predicting crime: It’s a science - Morgan Hill Times: Crime Fire Courts

Predicting crime: It’s a science

Algorithm predicts where the next crime will occur - so far it’s led to six arrests in a week

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Posted: Thursday, July 12, 2012 10:55 am

It’s only been a week since Morgan Hill police implemented new crime mapping and prediction software, and officers have already arrested at least six people on suspicion of various crimes, authorities said.

The city recently purchased the new system known as PredPol, which uses a complex algorithm to employ a technique known as “predictive policing” to identify 500-square-foot geographical areas throughout town where crime has happened – either over the last few days or several years – and where it is likely to occur again, according to Sgt. Shane Palsgrove.

The software cost $19,000 for a three-year contract, which includes ongoing tech support from PredPol.

For now, the department is using the software to focus on property crimes, including vehicle break-ins, burglaries and thefts. Such crimes rose by about 7 percent from 2010 to 2011, with 702 incidents of burglary, larceny and vehicle theft reported in 2011. Up until June 30 of this year, 250 such incidents were reported, according to city staff.

Officers patrolling the predicted crime zones identified by PredPol have arrested six people on suspicion of drug-related offenses, Palsgrove said.

Although police are currently targeting property crimes with PredPol, these crimes have a “direct correlation” to drug use, as users are known to commit theft to support their habits, Palsgrove said.

In one of the incidents, officers were patrolling a predicted crime area identified by PredPol when they saw and pulled over a suspicious vehicle, Palsgrove said. The female driver was arrested on suspicion of being under the influence of a controlled substance.

PredPol was developed by researchers from Santa Clara University and UCLA, and is based in part on sociological studies of criminal behavior, including the insight that burglars often visit the same area, Palsgrove said.

Morgan Hill Police Chief David Swing said the use of the software is part of the department’s strategy to use “intelligence-led policing” and to use resources more efficiently.

Individual officers might be hard-pressed to name the neighborhoods where incidents happen less often but where crime is still a problem, Swing said. And that’s where PredPol comes in.

“There are areas where crime is likely to occur, but we’re not as frequently called there, and PredPol keeps those areas on our radar,” Swing said.

The intricate system also gives small cities like Morgan Hill access to complex, in-depth analytic capabilities previously only available to large cities or businesses, Palsgrove said.

“The challenge, and what is really hard from the point of view of the crime analyst, is how do you balance crime patterns on different time scales? That's where the algorithm has the edge, sifting through years of data,” said Jeff Brantingham, a company co-founder and UCLA anthropologist.

The PredPol algorithm uses historical crime data going back eight years, including the time and locations of certain types of incidents, that are automatically entered into the system from the police department’s database, Palsgrove explained. But it also combines this data with the criminal, behavioral and sociological background the system’s developers incorporated into the software in order to predict where the next crime might occur.  

Each box representing a 500-square-foot area transposed onto a map of the city represents a “predicted area where crimes are likely to occur,” Palsgrove said. Patterns detected over a period of years and days figure into the algorithm that runs the software, and the zones are updated for each patrol shift based on the timeliest data, Palsgrove said.

“They move based on the data, and they can move as many times as twice a day,” he said.

The system uses local crime data going back the last eight years, Palsgrove added.

Authorities noted that a single red box in a neighborhood does not indicate a “hotspot” or an area where crime chronically occurs – but rather where it might occur in the near future.

The three most recent arrests using PredPol were drug-related: for being under the influence of a controlled substance, possession of methamphetamine and possession of drug paraphernalia. The arrests occurred within 24 hours of one other and within an about 3-mile radius (10 p.m. on Condit Road near Dunne Avenue, 1:45 a.m. Sutter Boulevard at Serene Drive, and 4 p.m. on Tennant Avenue and Condit Road.

On the coast, the Santa Cruz Police Department has been using a beta version of PredPol for just more than a year.

“It’s trying to take a proactive look,” said Zach Friend, Santa Cruz Police Department spokesman. “Maybe four or five crimes occurred on Main Street (for example) and a sixth crime might occur on the next block.”

The city of Santa Cruz is where PredPol’s corporate headquarters are. That city, whose police department has a $23 million budget and 94 sworn officers, uses the program to target residential, commercial, and vehicle burglaries, as well as stolen vehicles. They might later expand its use to include bike thefts, vandalism, aggravated assaults and batteries.

The city of Morgan Hill’s police department employs 33 sworn officers, and has an annual budget of about $12 million.

Since Santa Cruz started using PredPol, they have seen a 19 percent reduction in the targeted crimes in just one year, which Friend described as “widely successful.”

“To put it in perspective, that’s about 80 people in our city who woke up and didn’t find their home or business or vehicle broken into,” he said.

Furthermore, to an extent the software “equalizes experience levels,” as it gives neophyte officers an insight into the character and criminal history of certain parts of town that only veteran officers might have benefited from before PredPol was implemented, Friend said.

Officers also combine the use of PredPol with their training, such as when they respond to a crime identified by PredPol and they know to patrol the neighborhoods surrounding that red box, Palsgrove added.

Police are also working with the community to alert residents if they live in or near clusters that might reappear on a regular basis, Palsgrove said.

The Morgan Hill department wants to eventually apply the system to drug-related offenses and vehicle accidents, Palsgrove said.

Applying PredPol to traffic-related incidents could be even more useful to the public, Palsgrove said. If the data is shared with motorists, they might be able to respond by driving more safely and with more awareness in those areas.

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  • WilliamYancey posted at 11:43 am on Mon, Jul 16, 2012.

    WilliamYancey Posts: 390

    hh probably thinks he's being being clever.

  • hypocrisyhater posted at 8:12 am on Mon, Jul 16, 2012.

    hypocrisyhater Posts: 234


    MHPD put up a few job listings for positions they are trying to fill.

    Why don't you submit your resume? Turn away from the Dark Side.

  • WilliamYancey posted at 9:03 pm on Thu, Jul 12, 2012.

    WilliamYancey Posts: 390

    Six people arrested on drug-related charges. The prison-industrial complex must love this program.

  • that1scott posted at 3:00 pm on Thu, Jul 12, 2012.

    that1scott Posts: 3

    Anyone who has lived here long enough could tell you specific high crime areas. For starters, bulldoze the Village off of Crest.

  • Tony_R posted at 9:33 am on Thu, Jul 12, 2012.

    Tony_R Posts: 79

    Is this any better than Dirty Harry watching a parked car with engine idling from a diner across the street, while observing that cigarette butts are accumulating next to the car, coming to the conclusion that an armed robbery is progress in the bank? That's a sort of "predictive policing" that relies on officer experience, not whiz-bang gadgets.