The NYPD has hosted a weekly traffic statistics meeting for going on twenty years. Brass from the traffic enforcement division meet with precinct commanders experiencing an uptick in crashes and fatalities, and discuss dangerous intersections to focus their enforcement. But the tool that the NYPD uses to inform that meeting—to map traffic crashes involving pedestrians, cyclists and other drivers—has historically been kept private. Today, the NYPD launched TrafficStat, which does for traffic crashes what CompStat does for robberies, shootings, and domestic assault.

"Obviously any time that we help the public to see where we have particular problems, we make ourselves accountable in the process," said Mayor de Blasio during a Tuesday press conference to unveil the new website.

"We want the public to hold us accountable to the changes we have to make," he added.

The new bird's eye map will be updated every Tuesday ahead of the NYPD's weekly Friday meeting, according to Deputy Information Technology Commissioner Jessica Tish. A panel on the lefthand side of the map can be filtered by patrol borough and precinct, showing week, month, and year-to-date numbers for collisions, injuries and fatalities compared to 2015. A panel on the left filters for time of day, hour, and broad "collision type" and "contributing factor" categories—"following too closely," for example, or "failure to yield the right of way."

For example, in Brooklyn North last week, 11 cyclists and 27 pedestrians were injured in traffic. Of those cyclists injured, one was side-swiped on Broadway and DeKalb Avenue at 5:00 p.m. on the 21st. Another was rear-ended at 4:00 a.m. on the 22nd, at the intersection of Throop Avenue and Monroe Street. Cyclist injuries for Brooklyn North as a whole are up 37.5% over this time last year; pedestrian injuries are up 8%.

Before the launch of TrafficStat, the public's primary resource for crash data was Vision Zero View, a more simplistic map function updated monthly to show injury and fatality data. The map doesn't include the cause of the crash, nor does it include collisions without associated injuries or fatalities. It's also been spotty in its reliability, going four months earlier this year without an update. The NYC Open Data table for motor vehicle collisions is updated weekly and can be filtered by intersection and period of time to suss out specific streets prone to crashes, but it lacks the map function.

Tish stressed Tuesday that the statistics on injuries and fatalities are subject to change, and adjustments for one week will reflect in the next week's update.

The map also lacks data on traffic enforcement by intersection, which some critics say would hold the NYPD accountable for the so-called 'precision policing' it touts: focusing on the intersections that see the most crashes when ticketing drivers who speed and violate right of way. ("We're focusing additional resources on those locations and we're making sure that there is stepped up consequences," Mayor de Blasio said.)

The mayor accompanied today's TrafficStat launch with a report on traffic fatalities in the last month: 13 deaths between October 27th and November 27th, compared to 30 last year. He attributed the significant dip to a month-long NYPD enforcement crackdown that coincided with the end of daylight savings, when the evening rush hour becomes significantly more dusky.

"That focused enforcement had a big and positive impact," he said.

Transportation Alternatives Director Paul Steely White was less optimistic. Year to year, the statistics aren't as impressive: 204 traffic fatalities in 2016, compared to 209 this time last year. "A couple good weeks is encouraging, but the trend this year overall has been discouraging," he said.

Steely White added that his group has been pushing for a more radical data dump, including Collision Investigation Squad crash reports in their entirety. "That's where you can see what the precise causal factors were," he said. "I believe we are working towards that. Those individual reports tend to be very useful when you are trying to understand flaws with intersection design that have contributed to a crash."