Tuesday, July 26, 2016

Zombie Arguments in Bike Safety

Zombie says overtaking crashes are very rare, 
so why build bike lanes? Turns out 40% of fatal 
car-bike crashes are rear-enders. 

Recently I posted a story about Tom Palermo, his death, and the subsequent construction of parking protected bike lanes on Roland Avenue in Baltimore, where Tom died.

Shortly before the new bike lanes went in, there was a contentious community meeting attended by City officials. After the meeting, the officials confirmed that they would proceed with construction of the bike lanes, and they responded to a number of issues that had been raised.

Among the FAQs from the Baltimore DOT (on page 9) was this: "Since rear end crashes are rare for bicyclists, how is the change to cycle track protected by parked cars justified? Please provide statistics and references."

This argument has been around for a while, and it refuses to die. I'm not quite sure how you kill a zombie argument. I'm pretty sure you don't drive a stake through its heart - that's for vampires.

At first, I was going to let this go. After all, the Baltimore officials did a reasonably good job of rebutting it, and it would have been easy enough to let things lie. However, one of the lessons I took away from the story of Tom Palermo's death and the subsequent bike lane controversy was that "specious arguments must be rebutted in detail."

So maybe you can kill a zombie argument by talking it to death. Or burying it in facts.

The FAQs from the Baltimore DOT referred to a data sheet from the National Highway Traffic Safety Administration, which focused on fatal bicycle accidents and found that in 2013 "non-intersection" crashes accounted for 57 percent of fatal bicycle crashes.

It's possible to take this further. In 2014 the League of American Bicyclists put out a report on a study it had conducted, independent of the federal statistics. For a period of 12 months, it researched in detail every fatal traffic crash involving a bicyclist that it could find on the internet, documenting 628 crashes. The results were, as the report put it, "eye-opening":

"We learned, for example, that a much higher percentage of fatal crashes than expected were 'hit from behind' incidents." Of crashes with reported collision types, 40 percent were rear-end collisions.

Rarity Is a Matter of Perspective
So why do people think 40 percent of deaths is rare? Because rarity depends on perspective. In absolute terms, death on a bicycle is rare.

Currently this particular way of meeting your maker is running around 700 a year. The National Highway Traffic Safety Administration reports that 726 bicyclists died in car-bike crashes in 2014.

Meanwhile, total deaths from traffic accidents involving motor vehicles were 32,675. Even pedestrians died more than bicyclists - 4,884.

And then you can add in all the non-fatal crashes. Good numbers here are hard to find because the reporting criteria vary widely among reporting agencies, but here is one indication of the non-fatal mayhem on our highways: 39.2 percent of spinal cord injuries in the United States result from motor vehicle crashes.

And of course we could add crashes that don't involve cars. Bikes crash into other bikes, pedestrians, immovable objects, the ground. Such crashes are rarely fatal, but they can result in serious injury.

Small Compared to What?
So, yes, in absolute terms, not a lot of people die in bicycle accidents. But the rate at which they die is another issue entirely.

John Pucher and Lewis Dijkstra published an article in Transportation Quarterly in 2000 on this subject. They found that, per kilometer traveled, bicyclists in the United States are 11 times more likely to die than motorists. Pedestrians are 36 times more likely to die than motorists, on a per kilometer basis. On a per trip basis, pedestrians and bicyclists are about three times more likely to die than motorists. Think about this the next time you venture out to the grocery store. (See my previous post Death as an Acceptable Outcome.)

A car is the safest place to be on the street. There's a lot of vehicular mayhem, but the vast majority of miles that Americans travel, and trips that they take, are by car, so the shockingly high mortality rates for walkers and bikers get masked. As Pucher and Dijkstra put it, "the dangers of walking and cycling in America are not just perceived, they are real."

The Terror Factor
The idea of being rear-ended by a car while you're riding your bike down the street holds a very special kind of terror. Such an event is very likely to kill you, and you can't in most cases prepare or react, because you don't know it's going to happen. You're utterly powerless. You have no control or even influence in this situation. (Here's a story on a crash in Kalamazoo, Michigan, in June. Five bicyclists died, and four were injured. It was a group ride. The driver has been charged with second degree murder and operating while intoxicated causing death, among other things.)

There are bicyclists who live with this icy thought every time they get in the saddle. What's more, I think it's why many moms won't let their kids ride bikes in the street anymore. They don't care so much that Johnny may fall and skin his knee. It's death from out of the blue that keeps kids inside, playing video games and getting fat.

And if the driver isn't drunk and doesn't leave the scene, he or she is unlikely to get more than a slap on the wrist. It's basically a free kill. Homicide without consequences. At least for the perpetrator.

We need to rethink this. We need to think of protected bike lanes as anti-terror devices.


  1. I agree. To extend your "terror factor" argument I'd say that the primary purpose of the parking protected bike lane isn't "safety" but INCREASING THE AMOUNT OF CYCLING.

    And that's a Good Things because increasing the rate of cycling increases a bunch of stuff that is beneficial for everybody, not just those that ride bicycles.

    Such as:
    * traffic congestion improves because bike lanes have greater traffic capacity than car lanes
    * the safety of all road users (drivers, cyclists and pedestrians) improves
    * the health of the population improves
    * less money is spent on transportation, leaving more money to be spent on other things
    * social connections are increased
    * air pollution is reduced
    * noise pollution is reduced
    * reduced dependence on foreign oil

    1. This comment has been removed by the author.