The Vancouver Police Department is implementing a city-wide "predictive policing" system that uses machine learning to prevent break-ins by predicting where they will occur before they happen — the first of its kind in Canada.

The system analyzes historical records of break-ins around the city and generates predictions about where break-ins are likely to occur over two-hour intervals, within either a 100- or 500-metre radius.

Police chief Adam Palmer said that, after a six-month pilot project in 2016, the system is now accessible to all officers via their cruisers' onboard computers, covering the entire city.

"Instead of officers just patrolling randomly throughout the neighbourhood, this will give them targeted areas it makes more sense to patrol in because there's a higher likelihood of crime to occur," Palmer said.

Up to 80 per cent accuracy, police say

Palmer said property crime is fairly common in Vancouver and has predictable patterns. For example, it usually spikes in the summer months, when people leave windows open and take vacations.

The system was piloted last summer during one of those expected spikes. Palmer said the project focused on areas south of Broadway, where residential break-ins are the most common.

Things got off to a slow start as the system familiarized itself with the data, and floundered in the fall due to unexpected data corruption.

But Special Const. Ryan Prox said the system reduced property crime by as much as 27 per cent in areas where it was tested, compared to the previous four years.

The accuracy of the system was also tested by having it generate predictions for a given day, and then watching to see what happened that day without acting on the predictions.

Palmer said the system was getting accuracy rates between 70 and 80 per cent.

Not like Minority Report

When a location is identified by the system, Palmer said officers can be deployed to patrol that location. Though he said a number of suspects were apprehended during the pilot project, he said the goal is mostly a highly visible police presence in the flagged locations.

"Quite often ... that visible presence will deter people from committing crimes [altogether]," Palmer said.

Though similar systems are used in the United States, Palmer said the system is the first of its kind in Canada, and was developed specifically for the VPD.

While the current focus is on residential break-ins, Palmer said the system could also be tweaked for use with car theft — though likely not with violent crime, which is far less predictable.

Palmer dismissed the inevitable comparison to the 2002 Tom Cruise film Minority Report, in which people are arrested to prevent them from committing crimes in the future.

"We're not targeting people, we're targeting locations," Palmer said. "There's nothing dark here."