Cambridge Civic Journal Forum

March 14, 2018

The Marcia Deihl bicycling fatality

Cambridge City Councilor Craig Kelley has obtained a copy of the crash reconstruction report in Marcia Deihl’s fatal collision with a truck on March 1, 2015, and posted the report online. I thank Mr. Kelley for performing this public service.

My understanding is that a Freedom of Information Act request was necessary to obtain a copy. That is not as it should be. The public needs to know the how and why of crashes, to avoid them and guide policy.

Quick summary: Deihl rode out of the driveway on Putnam Avenue from Whole Foods, collided with the front bumper of the truck, which was headed east in the lane closest to the driveway, and went under its front wheels. Here. You can see the ghost bike in the image. (It is before the driveway but the crash occurred at or after the driveway.)

Half-trigger warning: this post isn’t relaxing reading and neither is the report, but they don’t include any gruesome images, or except for the last few pages or the report, descriptions more graphic than what you have just read.

So, what about the report?

Unfortunately, the investigation leaves questions unanswered, which it might have answered. Only in the synopsis at the start of the report does the State Police investigator repeat part of the report of Cambridge Officer Sullivan who interviewed the truck driver at the scene. Sullivan’s report says that the driver “checked to his right but didn’t see anything but snow so he started to pull over. He stated as he was pulling over he started to put on his hazard lights. He felt a bump and thought he ran over a snow bank.” He also said that he was pulling over to park and then walk to a construction site to see if it was ready for the dumpster he was carrying.

The report doesn’t raise, or answer, the question whether the driver was looking ahead prior to pulling over, as he was approaching the driveway. There was also no discussion of the role that snowbanks might have played in blocking sight lines. You will probably recall that the winter of 2015 was the snowiest one ever recorded in the Boston area. 94.4 inches had fallen from Jan. 24 through Feb. 22, 2015.

Deihl pulled out of the driveway either just as the truck was passing, or she passed it. The initial point of impact was the front of the truck and — as identified by a GPS recorder in the truck — it was going only 5 mph at that point (slowing to a stop).

One thing that calls out to me in the report is the intensive examination of the truck but cursory examination of the bicycle (p. 12 of the PDF, p. 7 of the report). What if, for example, Deihl’s brakes had failed? Were the steel rims of Deihl’s old English three-speed bicycle wet? Steel rims are as slippery as ice when wet, and rim brakes barely work then. The temperature reached 30 F on the day of the crash, which occurred at 3 PM, but snowmelt might have wetted the rims. Or did the bicycle have a coaster brake, in which case wet rims wouldn’t have been an issue? Did Deihl skid on packed snow or ice? Also the autopsy report is rather perfunctory. Medical condition leading to loss of control? — last page of the PDF. “Bicyclist rideout” crashes like this one are rare after childhood, suggesting to me that something unusual went wrong.

The key to this crash would seem to be why Deihl came out of the driveway and collided with the truck, rather than stopping to let it pass. But the trucker also pulled over to the right — Deihl may have turned right assuming that the truck would clear her. — page 9 of the PDF.

Deihl was required under the law to yield to traffic in the street before entering it from a driveway. If she pulled out of the driveway ahead of the truck, the trucker could have prevented the crash as long as it was not too late for him to avoid the collision by braking or swerving. He was at fault if he failed to look. If Deihl was passing him on the right, she would have been close to the side of the truck and probably in its right-side blind spot. And sight lines may have been blocked by a snowbank.

It’s incredibly frustrating that:

  1. The investigator didn’t know what he is doing in a bicycle investigation (scenario repeated with the Anita Kurmann fatality in Boston later the same year);
  2. It took a FOIA request to see the report;
  3. Advocates use these tragedies to justify whatever pet projects they have. (Sideguards, says Alex Epstein. They would be irrelevant in this collision with the front of a truck: more about them here. Separate bike traffic from car traffic, says Pete Stidman. Just how would a sidepath have worked on a day when the street was lined with snowbanks is another valid question. Most likely, it would not have been usable. Comments by Epstein and Stidman are here. Neither of them had seen the report when they made their observations.)
  4. Advocates are avoiding adequately informing bicyclists about the hazards of trucks and how to avoid them.

Well, the advocates at the American Bicycling Education Association are an important exception. I am proud to be an instructor in its program. An animated graphic on safety around trucks is here and if you click on the title at the top of the page, you can find out how to sign up for a course (online or in person) which will cover that topic and much more.

I thank Paul Schimek for many of the observations in this post, and for drawing my attention to the availability of the crash report.

And again, I thank Craig Kelley for making the report available.

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