Digging in: How Many Crashes Are Due to “Bicycle Factors?”

Bike-Helmet_1.jpgCharles Komanoff at Right of Way has churned out an initial analysis of the City’s bicycle injury and fatality study. Here is his take:

New York City just released its first-ever study of bicycle injuries and fatalities. There’s good news and bad news. The good news is that four City agencies (health, transportation, parks and police) admitted, finally, that bicycling is good for New York City, and pledged to expand the City’s cycling infrastructure. The study also didn’t indulge in the NYPD’s habitual victim-blaming in cycling fatalities, a significant though unacknowledged shift.

Going forward, the involvement of the Dept. of Health may help move the discussion from harping on the dangers of cycling to highlighting its health benefits.

But here’s the bad news: The study has many methodological flaws and misleading findings, leading it to over-emphasize helmets and bike lanes and neglect the need for universal street safety. And the study completely neglects the fact that most fatal crashes are caused by aggressive, self-entitled drivers, and laissez-faire policing that allows motorists to literally get away with murder.

The study attributes 42% of all fatal bike-vehicle crashes to "bicycle factors," 20% to "vehicle factors" (i.e., drivers), and 36% jointly to both cyclists and drivers (another 2-3% of cases couldn’t be coded). That’s an improvement from the NYPD’s made-up "statistic" that 75-80% of biking fatalities are solely the cyclists’ fault. But it’s still deeply misleading. I know because I was given access to the NYPD’s cause-coding for three of the years studied (1996-98).

I headed up the team at Right Of Way that analyzed 1995-98 fatal bike crashes and wrote RoW’s Only Good Cyclist Report (PDF file) in 2000. My review of the NYPD’s crash analysis found them rife with errors. In one case, a driver ran a red light and struck and killed a cyclist proceeding lawfully through an intersection; The NYPD gave the cause as "Bike Thru Red Traffic Signal Light And Struck By Vehicle" and actually assigned a Bike Factor of "Traffic Control Disregarded." Similarly: a cyclist was crushed when a Mack truck made a right turn directly into his path. NYPD said, "Unsafe Bike Operator Turned Into Vehicle And Was Struck By Turning Vehicle" and assigned a Bike Factor of "Unsafe Lane Changing," even though it was the truck that changed lanes unsafely and turned into the cyclist, who had been traveling straight with the right of way.

I found that only 20% of the fatal bike-vehicle crashes could be attributed to "bicycle factors" (vs. the City’s 42%), while 44% were the exclusive result of "vehicle factors" (vs. the City’s 20%). The remaining 36% were the fault of both cyclists and drivers (the same as the City’s tally). In effect, my analysis turned the City’s cause factors upside down.

Diagnosis dictates treatment. If driver aggression or inattention is killing cyclists, the answer is to change that behavior. To say the very least, the study missed a priceless opportunity to tell it like it is.

  • Rich Conroy

    The problem with this (Charlie’s) analysis is that any discussion of cyclist error as a factor in fatal crashes gets dismissed as “blaming the victim”. So the only thing left to discuss is “aggressive, self-intitled” and “inattentive” drivers.
    As any cyclist knows, the problem of dangerous driving is real. But to ignore or downplay the role of dangerous cycling is self-defeating for the cycling community. We need to look at the whole picture, including cyclist choices, not just the drivers. Stand on any street corner, or observe cyclists at night. How many cyclists do things that are very dangerous to themselves in traffic, like flouting traffic rules or riding without lights at night? Why don’t we cyclists talk about these things? Because we get told that “we’re blaming the victim.” It’s almost as if cyclists can do no wrong, and motorists can’t do anything right. That may make us feel all righteous, but it’s poor social science and health science analysis. Others aren’t so constrained by this kind self-censorship and imbalanced thinking. Re: Carolyn Curiel’s article yesterday on Streetsblog yesterday, where she looks at motorist AND cyclists behavior.

  • Rich — your premise that I and my Right Of Way compatriots refuse to acknowledge cyclist error is belied by the fact that I coded 20% of the cyclist fatals as bicyclist-caused (with another 36% as jointly caused by cyclist and driver). You seem to think that we started with a “blame the driver, not the cyclist” idee fixe, when in fact what we gleaned from analyzing the fatals (as well as ten times as many pedestrian fatals) was a preponderance of driver culpability. In any event, we hope to post the data soon so you can see for yourself.

  • ddartley

    I don’t want to stir up prejudices, but I must say the cop who showed up at my dooring yesterday treated me the whole time as if I had done something wrong. It was COMPLETELY the taxi’s fault and not mine.

  • Daniel Millstone

    Programs to change deeply-set behaviors of drivers and cyclists may have less impact than engineering solutions which intervene in the process. Although we’ve all seen drivers and cyclists who act bizzarely, trying to figure out who did the wrong thing may be a wild-goose chase.

    Can we group bicycle-vehicle crashes (fatal and not) by some other categories than fault. How many crashes occur in the course of a right hand vehicle turns where is bike is going straight? What sorts of solutions could address those incidents?

  • J:Lai

    Daniel Milstone has an excellent point. Assigning fault is difficult and fraught with the preconceived prejudices of who is entitled to what part of the street. I routinely see both drivers and cyclists acting in ways that are dangerous, but in which both parties could probably justify their behavior based on what they think the other party should be doing.

    This can probably be adressed much more effectively as an engineering problem which minimizes the number of dangerous interaction between drivers and cyclists, than as a problem of re-educating people to behave in ways that they don’t naturally want to behave.


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