“Predictive policing” is happening now — and police could learn a lesson from Minority Report.
David Robinson Blocked Unblock Follow Following Aug 31, 2016
In the movie Minority Report, mutants in a vat look into the future, and tell Tom Cruise who is about to commit a crime, so he can arrest the offender before the crime happens. Spoiler alert: Those mutant fortune tellers turn out not to be infallible, but the cops treat them as though they were. Law enforcement’s blind faith in a tool that doesn’t always work — a tool that can easily finger the wrong person, with terrible results — provides the central tension for that blockbuster film.
Real police are now at risk of making a similar mistake. But this time the results are in the street, not at the box office. Today’s cops don’t rely on soothsayers, but they do increasingly use software to forecast where future crimes may happen, or who may be involved. And they are nowhere near skeptical enough of the forecasts those computers are making.
Today, a national coalition of 17 advocacy groups is raising the alarm about this, with a shared statement highlighting six ways that this trend threatens civil rights.
These groups all agree — the current rush toward predictive policing is wrong.
Upturn, where I work, helped draft the new statement, and today we’re releasing a report designed to empower you to get beyond the hype and make up your own mind about what the industry calls “predictive policing.” As lead author of that report, here’s what I’d like you to know.
Police can easily trust these tools too much.
People often overestimate the accuracy, objectivity, and reliability of information that comes from a computer, including from a predictive policing system. The RAND Corporation, which has done the best studies to date, is a famously buttoned-down kind of place. But they’re just as bothered by this problem as I am. They write: “[p]redictive policing has been so hyped that the reality cannot live up to the hyperbole. There is an underlying, erroneous assumption that advanced mathematical and computational power is both necessary and sufficient to reduce crime [but in fact] the predictions are only as good as the data used to make them.”
Police data about crime paints a distorted picture, which can easily lead to discriminatory policing patterns.
These systems only predict which crimes police will detect in the future — and that creates a distorted picture. As an eminent criminologist once said, “[i]t has been known for more than 30 years that, in general, police statistics are poor measures of true levels of crime.”
In the context of predictive policing, statistics generated by the policing process are often treated as though they are records of underlying criminal behavior. But these numbers are a direct record of how law enforcement responds to particular crimes, and they are only indirect evidence about what is actually happening in the world. Criminologists argue that “[a]rrest, conviction, and incarceration data are most appropriately viewed as measures of official response to criminal behavior.”
Of course, it makes sense for police to be responsive to community needs. Different communities served by the same police department often do have different needs, and different levels of need. That means officers will see more of what goes on in some neighborhoods than they will in others. But it is dangerous to treat the results of that process as though they were a completely neutral reflection of the world.
As data scientist Cathy O’Neil explains, “people have too much trust [that] numbers [will] be intrinsically objective.”
Rather than changing their tactics, police who use predictive tools have tended to focus on generating more citations and arrests. I read everything I could find about how police are actually using predictive policing tools. The consistent answer was that police aren’t being guided toward different or more humane tactics. Instead, where the computer says to focus, the police do more enforcement. Which worsens the data problem.
Data could be used in ways that strengthen civil rights, but we’re missing that opportunity.
This, to me, is one of the most exciting things we found in our research. To quote from our report:
In most of the nation, police currently measure outcomes and assess performance based on only some of the activities, costs, and benefits that matter in policing…
Serious violent crimes will always be important. But violent crime doesn’t reflect the full scope of community concerns…
[E]xperts on police performance measurement have long argued that police should track all uses of coercive authority so they can better promote public safety with minimum coercion…. And research on police performance measurement consistently calls for surveying victims to gather their feedback on the police officers with whom they interact.
Beyond the basic goal of constitutional, lawful policing, measuring factors like these could allow the poli