Thursday, February 23, 2017





Thanks to the Huffington Post.

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City's "transition to a new reporting system" on traffic accidents

Carolyn Tyler

In its new Collisions Report, the MTA offers a disingenuous explanation of what's been happening in the last several years about how the city has been recording traffic accidents:

Since the previous 2010-2011 Collisions Report published in 2012, production of this report was delayed due to problems validating data during the transition to a new reporting system that relies on local data rather than state data. 

Until 2012, the SFMTA received collision data through the Statewide Integrated Traffic Records Systems (SWITRS), which is maintained by the California Highway Patrol (CHP). California Vehicle Code (CVC) Section 20008 requires that local governments send their police collision reports to the State. The CHP then enters the data into its own database and reports it as official data. However, there has traditionally been a one- to two-year lag for an annual set of data to be considered official by the CHP. Since 2013, collision data has instead been reported directly by the San Francisco Police Department (SFPD) and validated by the Department of Public Health (DPH) and the SFMTA.

The false implication here is that it was the "lag" in reporting traffic "collisions"---aka "accidents"---that was the problem and that the city is now in "a transition to a new reporting system."

The real problem is alluded to on the next page (4):

While injury collisions tend to be reported more consistently than non-injury collisions, unfortunately not all injury collisions are captured by police reports. These include crash types such as solo falls by people on bicycles and certain types of pedestrian-involved crashes. The extent of this underreporting will be better understood with DPH’s comprehensive transportation-related injury surveillance system, which will be released later this year.

This paragraph footnotes the UC study only I've written about here in Progressive Land. (Since it's behind a paywall---why should a study by public employees be behind a paywall?---I've transcribed it here.)  It also footnotes a 2005 study that found the city was also under-reporting pedestrian accidents

Apparently the Examiner, the Chronicle, the SF Weekly, and Streetsblog found the implications of the UC study so disturbing to the official city pro-bike consensus---that riding a bike in the city was a lot more dangerous than the public has been told---they failed to even mention it, though the New York Times found it newsworthy. The Bay Guardian didn't write about the study, either, but Steve Jones at least acknowledged its existence in an exchange with me.

Seems like I've been more interested in the safety of city cyclists than City Hall, the local media, Streetsblog, and the Bicycle Coalition.

Look at the timeline: The UC study was published in December, 2012. The NY Times story on the study was published in October, 2013, which was the first I learned about it. The last Collisions Report---the one before this one---was published in August, 2012, and the rest was silence until late last year when this report was published with no notice or press release.

The Department of Public Health’s "comprehensive transportation-related injury surveillance system" referred to above is all about reporting/tallying traffic accidents---and Vision Zero. It doesn't do the kind of analysis Commander Ali did a few years ago that studied in depth all fatalities for a single year. Or even the kind of analysis the Collisions Report does of intersections on pages 15-24.

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