Some crash stats

[Rauschpfeife]

Digging some more on the DOT datasets Myles found for us, I did a superficial analysis of the "contributing actions" recorded, for bike/ped and car-only crashes, respectively, in Portland and the adjacent 3 towns. Details in the attached spreadsheet. 

One glaring fact: in the bike-ped crashes, about 50% have no contributing action given. In the car-only crashes, it's 16%. 

Also, wryly: "Drove too fast for conditions" is recorded for 5.1% of car-only crashes, and 0.6% for bike/ped crashes. Seems it's only the slow drivers who are running into people on foot and on bicycles. 

Note that the number of actions recorded is greater than the number of crashes, since more than one action is reported for some crashes. 

-- 

Best, 

Michael Smith

anacharsis.substack.com

[John Brooking]

I’d conjecture that the 50% “No cause given” indicates either a lack of training in documenting car/bike crashes, or lack of motivation, or both.

Also interesting to me that the next highest by far is failure to yield. I’d like to know if that’s on the part of the motorist or the bicyclist. Probably a mix, but what ratio? And on motorist failure to yield, what were the positions of both operators? Were blind spots involved, or was the bicyclist far outside the motorist’s forward field of vision?

John Brooking

Cyclist, Cycling Educator, Technologist

https://www.facebook.com/CyclingSavvy4ME/, http://cyclingsavvy.org

--
You received this message because you are subscribed to the Google Groups "Portland Bicycle and Pedestrian Advisory Committee" group.
To unsubscribe from this group and stop receiving emails from it, send an email to PBPAC+un...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/PBPAC/CAERgV99TRxNX_75MWxaSqA9_5MbdEFRjRAgJ5HC%2B8rBtJ_mmjw%40mail.gmail.com.

[Rauschpfeife]

All good questions. It isn't always clear from the database entry just which "action" applies to which party. The database entries are essentially boiled-down from the police reports. Those would enable us to refine the picture. The actions are listed in two categories ("unit 1" and "unit 2", usually the driver and the ped/cyclist respectively). But it appears that the cop or the transcriber sometimes lists things under "unit 2" that don't make any sense for a walker or a cyclist (speeding, for example). I could break it down by unit 1 and 2, which might give us *some* indication of what the cop's intent was. I'll give that a try and see what it looks like. 

I personally think the abundance of no-action reports for ped/cyclist reports is mostly police indifference rather than incompetence, but I'm a notorious cop-skeptic. 

-- 

Best, 

Michael Smith

anacharsis.substack.com

To view this discussion visit https://groups.google.com/d/msgid/PBPAC/CAJg%3D2oyk7SWgs9nh_YqLievUNgNmZcs4tmRj4A0n%2BW5oJxzeKA%40mail.gmail.com.

[Rauschpfeife]

Attached, a revised version of the spreadsheet, with the causes broken down by "unit 1" (usually the driver) and "unit 2" (usually the victim). As you'll see, there are some oddities attributed to "unit 2". 

-- 

Best, 

Michael Smith

anacharsis.substack.com

On Mon, Dec 29, 2025 at 3:42 PM John Brooking <johnbr...@gmail.com> wrote:

To view this discussion visit https://groups.google.com/d/msgid/PBPAC/CAJg%3D2oyk7SWgs9nh_YqLievUNgNmZcs4tmRj4A0n%2BW5oJxzeKA%40mail.gmail.com.

[Zack Barowitz]

Interesting. Basically there is little consistency in how this stuff gets reported.

Zack

To view this discussion visit https://groups.google.com/d/msgid/PBPAC/CAERgV9-EMpwUOFTp06O_e-g99%2Bke1SsJ8nu26H%2BOnaR3vyWbuw%40mail.gmail.com.

--

207-838-6120

917-696-5649
ZacharyBarowitz.com

ATTENTION:
The information in this electronic mail message is private and confidential,
and only intended for the addressee. Should you receive this message by
mistake, you are hereby notified that any disclosure, reproduction,
distribution or use of this message is strictly prohibited. Please inform
the sender by reply transmission and delete the message without copying or
opening it.

[Rauschpfeife]

True. Even cop indifference isn't entirely consistent. That is, I was actually surprised at how *often* the P'land police reports attributed some kind of mal- or mis-feasance to the driver. When we did this exercise in New York, some years back, it was actually rare for the cop to do that. But still, the 50% where clearly nobody really looked into the thing tells its own story. 

-- 

Best, 

Michael Smith

anacharsis.substack.com

To view this discussion visit https://groups.google.com/d/msgid/PBPAC/CAE741VDvXKM962v2kyUPyLrvrJFqz6HNsdsLoXKB9d-ZGVOW_A%40mail.gmail.com.

[John Brooking]

I'm actually suspicious at how one-sided the breakout is between motorist and cyclist, using the interpretation of "Unit 1" as the motorist, although you've said that's a little unclear.  Although I know these are all the mentioned factors and not just the primary legal fault, I have been given to believe that legal fault is usually about half and half in most crash studies. Here, 98% of the factors are attributed to the motorist (excluding the "No cause" number)! That may make us feel better as bicycle advocates, that we are the good ones, but I'm not sure I believe it. Most noticeably: Only 1 of the 379 failures to yield were the bicyclist? But 6 of the 25 "followed too closely" were the bicyclist? (I did run into a car from behind once, when we had just started up at a green light, then he slammed on his brakes in front of me because we had been arguing and he was mad at me. But I'd say that's an outlier.)

John Brooking

Cyclist, Cycling Educator, Technologist

https://www.facebook.com/CyclingSavvy4ME/, http://cyclingsavvy.org

To view this discussion visit https://groups.google.com/d/msgid/PBPAC/CAERgV9-uou61eZk1V55w19JSRLtpCtATWazzYFh5OXRt64P3tw%40mail.gmail.com.

[Rauschpfeife]

The few police reports I've seen (half a dozen) seem consistent in treating the car as unit 1 and the ped/cyclist as unit 2, but I bet the cops and/or the data conversion process get it wrong occasionally. Bear in mind that the DOT database is a redaction of the police reports, so there's some kind of process there; I only hope it's not some poor schmo at a keyboard. 

-- 

Best, 

Michael Smith

anacharsis.substack.com

To view this discussion visit https://groups.google.com/d/msgid/PBPAC/CAJg%3D2oxBfDPtqAsKR6QsNqcst0pLgy%3D9Bcyf5wZw8R_G%3D09_Ug%40mail.gmail.com.