A followup today on our report last week about Southwest Precinct Lt. Pierre Davis telling the West Seattle Crime Prevention Council that SPD would soon use Predictive Policing – a new way to use crime data to work on preventing crime, not just responding to it. This morning, the mayor and police chief announced its debut in the Southwest and East Precincts. Official announcement, with details on how it works, ahead:
Mayor Mike McGinn and Police Chief John Diaz announced today that new “Predictive Policing” software has been deployed in the East and Southwest Precincts. The software was designed by the University of California, Los Angeles in partnership with the Los Angeles Police Department. It has been used by police departments all over the nation to reduce crime through deep analysis of crime and location data.
“This technology will allow us to be proactive rather than reactive in responding to crime,” said Mayor McGinn. “This investment along with our existing hot spot policing work will help us to fulfill the commitments we made in the 20/20 Plan to use data in deploying our officers to make our streets safer.”
“The Predictive Policing software is estimated to be twice as effective as a human data analyst working from the same information” said Police Chief Diaz. “It’s all part of our effort to build an agile, flexible and innovative police department that provides the best service possible to the public.”
Based on models for predicting aftershocks from earthquakes, Predictive Policing forecasts the locations where crime is likely to occur, down to a geographic area as small as 500 feet by 500 feet. It works by entering all crime and location data dating back to 2008 into a complex algorithm that generates a prediction about where crimes are likely to take place on a certain day and time. Officers are provided with these forecasts before beginning their shifts, and are assigned to use their “proactive time” between 911 calls to patrol those areas.
Very few pieces of data are needed to make predictions – the software works from just types of crime committed, location and time. No information on who committed crimes in the past or any other identifying information is included in the data set. The SPD 20/20 team worked closely on implementation of this software to ensure that it meets community expectations for privacy and addresses concerns about bias.
“We anticipate that this software will help us in our work to eliminate institutional bias in the Seattle Police Department” said 20/20 leader Assistant Chief Mike Sanford. “With Predictive Policing, we’re sending officers right to where we know the crime is, helping to take any unconscious bias out of the equation.”
Predictive Policing is currently analyzing only property crimes in East and Southwest Precincts, but the department anticipates rolling it out in every precinct in April 2013, with analysis of other types of crime soon to follow.