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All Tomorrow's Crimes: The Future of Policing Looks a Lot Like Good Branding 

Wednesday, Oct 30 2013

Page 5 of 6

Similarly, when SF Weekly requested an independent third-party analysis of PredPol's performance in Salinas, the city replied that no such verification has ever been carried out. Nor has an independent analysis been conducted in PredPol's hometown of Santa Cruz. Instead, Santa Cruz provided a "radar" report assembled by PredPol's Mohler, which according to the Santa Cruz police "can go back a maximum of 3 months to compare the accuracy/effectiveness of PredPol." In addition, the Santa Cruz police provided academic journal articles authored by PredPol's Mohler and Brantingham, both of whom have a financial stake in proving the method works.

Philip Stark, chair of the statistics department at UC Berkeley, reviewed these documents and evaluated the company's claims of reducing crime. "I'm less than convinced," he says. Stark has studied demographics, climate models, and even methods of earthquake prediction. He's also been an expert witness in lawsuits involving truth in advertising, behavioral targeting, credit risk models, and oil exploration. Stark was skeptical.

"Does using it lead to a decrease in the crime rate?" he says. "You would need to do a comparison of similar-sized cities, with similar conditions, similar trends in their crime rates, with one group of cities using predictive policing, and the others not. Then you'd compare them to each other."

"A comparison of the same jurisdiction to itself means nothing," he continues. "Crime fluctuates normally from year to year in the same city." This is, however, exactly what PredPol and the LAPD have done in claiming that predictive policing reduced crime in L.A. PredPol made the same claims in Santa Cruz, and recently in Richmond, comparing year-over-year crime rates within a single city.

"By just doing it once, last year to this year, that's like a coin toss," says Stark.

"I know the guys behind PredPol. They're pretty smart," says Jerry Ratcliffe, the chair of Temple University's department of criminology. Ratcliffe has collaborated on multiple crime prediction projects, including development of software similar to PredPol's for another company in Pennsylvania. He says, however, that predictive policing is "relatively new," and as a technology it's "not proven by a stretch."

According to Ratcliffe, predictive policing methods simply haven't been subjected to rigorous independent testing that would allow a vendor to claim its product reduced crime and caught offenders. "Testing these systems requires experimental conditions which are rarely conducted in policing and crime prevention, unfortunately." And even if PredPol or another predictive policing algorithm works, that's not enough. "A computer will never prevent crime," says Ratcliffe. "Computer outputs need to tell police where crime is likely to happen, but then police need to come up with a policy response."

Ed Schmidt, a criminologist and veteran police officer, believes in the concept of predictive policing, but he has serious reservations about PredPol's supposed effectiveness. Schmidt just completed a review of predictive policing efforts across 156 cities, and says there is little actual data that predictive policing works. Even if it does work, there's no guarantee that using it will actually reduce the overall rate of crime in a city.

"I look at this all with skepticism," says Schmidt. "Where are they coming from, how are they implementing it? Are they just displacing crime between divisions? Are they just displacing crime from one precinct to another? Mine goes down, yours go up?" If that's the case, says Schmidt, then PredPol's product isn't a tool to reduce crime so much as to shift it around, and cops have been doing that for decades already through both hotspotting and street patrols: When police suppress crime in one part of a city, it moves to other areas where police aren't hovering.

Schmidt also worries that flashy predictive policing software like PredPol's might only be having a public relations impact, that it's more about looking 21st century and tough on crime. "For the amount of money they're spending, it's going to generate great press and it makes everybody feel safer," says Schmidt. "The cops and city can then say, 'We've employed the state-of-the-art stuff.'"

"The context here," according to Schmidt, "is that everybody's budget is dropping. So you have to be an innovator. You have to show your city council that you can do more with less, and effectively battle crime."

Stark, meanwhile, criticized the academic publications of Brantingham and Mohler upon which PredPol claims to have based its software algorithms. Unlike many scientific journal articles that are only ever read by a few dozen Ph.D.s working in the same field, PredPol has sent Brantingham and Mohler's work to many police departments as scientific proof of their product. The Santa Cruz Police Department has copies of Mohler and Brantingham's article from the American Journal of Statistics on hand.

Stark calls this paper a "thought experiment." The paper claims that crimes occur in patterns similar to earthquake aftershocks, and that based on this the location of future crimes can be predicted. "Earthquake prediction algorithms don't work," says Stark.

"It's a vague analogy," he says. "It's an observation that sometimes there are crime sprees. There is a little bit of physics with earthquake aftershocks. There isn't in crime."

If PredPol's links to earthquake prediction are questionable, its connection to militarized studies of insurgents and civilian deaths is potentially even more troubling. PredPol's web site and the company's presentations and sales materials available online, and obtained from cities through public records requests, do not mention the software's military origins. Nevertheless, Brantingham is a key scholar in the U.S. military's network of academics, and his UCLA lab is supported by the Air Force and Army. This trend of militarizing the police by outfitting them with military-grade weapons — or in the case of PredPol, using military-funded research and technology to change the ways cities are patrolled — has come under intense scrutiny in recent years. Reformers on both the right and the left worry that police tools and tactics developed for overseas battlefields will strip away Constitutionally-protected rights.

As recently as Sept. 6, PredPol's Fowler again pressed Merritt and Suhr on the date for SFPD's PredPol deployment. Right now, SFPD has no contract with PredPol. Merritt tells SF Weekly that the department is concerned about launching the program prematurely. She maintains that the SFPD "did the analysis with PredPol," and that the company showed that its product works. She added the caveat, however, that PredPol's proofs to the city compared the software's predictions to random predictions. "A captain isn't just doing random patrols right now," Merritt says.


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