Bicycle Austin forum

Jack

Member

Registered: 2013-03-27

Posts: 344

San Diego Study on Relative Fault in Collisions

http://www.utsandiego.com/news/2014/nov … tatistics/ 
For a few years running, where fault is found in auto-bike collisions, cyclists were found more at fault in more than half of cases.

But it's not a big difference.  56-60% were cyclist more at fault.  6% of cases the one more at fault not found.  Wiggle room on small samples, methodology, etc. makes it seem about even, in my estimation.

MichaelBluejay

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From: Austin, TX

Registered: 2008-05-26

Posts: 1,466

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Re: San Diego Study on Relative Fault in Collisions

Why am I not surprised that as for our local Effective Cycling member, whose group revels in things like opposing bike lanes and criticizing cyclists who aren't a part of their specialized religion, the only time he quotes a study about relative blame, picks the one that shows cyclists are mostly to blame for collisions...and ignores all the other studies that show the exact opposite.  Predictable, predictable, predictable.  This is why I tire of EC in general, and Jack specifically.

So let's take a look at the study in question: It relied on police officer assessment of blame(!), so it's basically just so much bullshit.  We have tons of experience showing the bias of police against cyclists.  For just one, I'm reminded of the recent case where a driver illegally hit a cyclist, the police naturally concluded the cyclist was at fault because he was a cyclist and issued a ticket, the cyclist got video proof that it was the driver's fault, and the police REFUSED TO EVEN LOOK AT THE VIDEO EVIDENCE, saying ""We all know how bikers behave. It must have been your fault. C'mon. You are a biker." (source)

Every time someone posts any evidence showing the advantage of bike facilities, Jack is there to scream "Bad methodology!  Bad methodology!  Not scientific!"  And then he posts this piece of crap and doesn't even note the elephant in the room that the blame assessment was made by police officers.

For many years, the front page of Bicycle Austin site has a link to a study that showed drivers to be at fault in 90% of car-bike collisions. (source)  There are others that draw similar conclusions.  But no, the one study Jack posted is the single one that draws the blame-the cyclist conclusion.

Jack

Member

Registered: 2013-03-27

Posts: 344

Re: San Diego Study on Relative Fault in Collisions

Whew!  Posted it FYI, and with a note flagging small samples and methodology; didn't vouch for it. Sorry about that side of your bed, man. 

If you would like me never to post here again, just ask!

Last edited by Jack (2014-12-04 16:50:29)

Darron

Member

Registered: 2014-05-22

Posts: 131

Re: San Diego Study on Relative Fault in Collisions

I did not take the original posting in a negative light, just as an FYI like Jack said.  I agree with Michael that you gotta take these studies with a grain of salt when it comes to who is at fault as the police bias is probably the biggest factor in assessing blame than anything else.  Now I don't have the time nor inclination to do a full study but I'm sure one could tease out the effect of the police force on fault assessment as just a quick Google search shows wildly varying fault assessment by location:
Toronto: Cyclists 10%, http://www.ibiketo.ca/forum/general/cyc … ts-toronto
AZ: Cyclists 44%, MN: Cyclists 40%, DC: Cyclists >50%, http://www.npr.org/blogs/health/2011/05 … e-at-fault
CA Highway patrol: Cyclists 60% (although the story cites another study accusing bias in police reporting), http://iteamblog.abc7news.com/2007/05/b … ars_c.html
Los Altos: Cyclists 74% (mostly due to unsafe speed, really Los Altos? Really?), http://streetsblog.net/2012/09/21/polic … -the-cake/

My guess is these studies tell us more about the police procedures in various locations than anything about who is at fault in cyclists-auto accidents.  Good rule of thumb to follow: always, always, always insist on a police report if you are in an accident (Bike, car, tauntaun, or otherwise).

D

Jack

Member

Registered: 2013-03-27

Posts: 344

Re: San Diego Study on Relative Fault in Collisions

Grain of salt always, of course. The thing that most struck me about the conclusion of the study was the emphasis on "most" collisions being assigned to the fault of cyclists when the numbers might as easily be characterized as "about half" even if technically a few more cyclists got more of the blame more times than the motorists did.  "Most" is in a sense accurate for the numbers, but also seems like a distortion.  I am wary that the take away from "most" being the fault of cyclists is too often distorted into "usually" or even worse into "every time more at fault than the motorist."  "About half" would likely put cyclists in a better light as memory fades about the details.

I will add--yeah, cops can be biased against cyclists.  I take that as a given, not an elephant in the room.  Obviously, that tells us a bit more about the "'bout half" conclusion.

Last edited by Jack (2014-12-05 03:00:10)

Jack

Member

Registered: 2013-03-27

Posts: 344

Re: San Diego Study on Relative Fault in Collisions

Interesting article from Austinite Andrew Tilin in OUTSIDE magazine  http://www.outsideonline.com/outdoor-ad … r-War.html  which is a very nice piece. 

Only relation to this thread is that the article quotes a 'statistic' -- unsourced -- which also boils down to roughly half and half.  " . . .  Hottman consistently quotes a statistic that many riders don’t know or choose to ignore: roughly 47 percent of all bike-car mishaps happen because riders are at fault. That figure is debatable—there’s no national database, and Hottman’s use of it derives from small-sample studies, media accounts, and her own experience working on cases over the years. "