Car v. bicycle crashes: Motorists at fault just over half the time, police report says

In this week's feature, "On a Roll," we take a look at the growth of cycling in Denver and the potentially fatal consequences. As more Denver residents are hopping on bikes, tensions on the road seem to be at an all-time high -- and collisions between bikes and cars certainly are. Here, we dig deeper into a recent police report on where crashes are happening, who is at fault, and how the problem, at least by some measures, is worsening.

The August 30 "Auto / Bicycle Accidents" report, on view below in its entirety, comes from the Data Analysis Unit of the Denver Police Department; it was prepared for the Mayor's Bicycle Advisory Committee, or MBAC, a volunteer group that advocates for better bike infrastructure and other cycling interests. The report comes after a summer that far exceeded previous years in terms of the number of bike-vehicle collisions.

As we noted in our feature, the city is preparing to launch a bike safety campaign that will seek to push positive messaging about sharing the road, following the laws, respecting cyclists, etc. The campaign was first officially discussed in August during a somewhat heated meeting between several city agencies, civic groups and bike advocates. That discussion occasionally derailed into a philosophical debate on how cities can prevent collisions, who bears the burden of this challenge, who is more often at fault and how culture around biking can change.

Many in attendance agreed on one thing: More data -- and more specific data -- would help everyone better understand the problem.

At that time, MBAC was already asking DPD for this information, and a few weeks later, the department released the report to the coalition.

Here are some key findings:

• Auto/bicycle accidents have been on an increasing trend over the past ten years. Year-to-date, auto/bicycle accidents have increased 13.2 percent over a ten-year average.

• Accidents in May and June this year were significantly higher than the average for those months over the last ten years.

• In 2011, the top three neighborhoods for auto/bicycle accidents were: Lincoln Park, Capitol Hill and City Park West.

• The top three neighborhoods for auto/bicycle accidents from January through August 23, 2012 were Five Points, Capitol Hill and Civic Center.

• Over a ten-year average, 61 percent of accidents occurred between noon and 7 p.m.

• The majority of auto/bicycle accidents occur on weekdays.

• The majority of violations written for bicycle infractions were: bicycles subject to traffic control devices and bicycles subject to traffic laws.

• The highest number of violations for citations tied to auto/bicycle crashes were bicycles subject to traffic laws and riding on the sidewalk.

• Motorists are at fault slightly over 50 percent of the time in auto/bicycle accidents.

Continue for analysis of these findings and more specifics from the DPD report. The last finding in that list -- that motorists are at fault slightly more often than bikes -- is perhaps one of the most controversial. While bike advocates like to emphasize that many in Denver are drivers and cyclists -- making the "us vs. them" argument false -- debates about cycling and sharing the road can quickly devolve into the blame game. Which is understandable considering some of the bizarre, albeit very extreme, cases of recent bike-related rage, including a nonstop honker harassing cyclists, an allegedly drunk cyclist swerving in front of vehicles in Boulder and pulling out a knife and this week, a barbed-wire trap that knocked a woman off her bike.

But as Piep van Heuven, executive director of advocacy group BikeDenver, says: "The hardest thing...is that when you begin to talk about the tensions between people driving cars and people riding bikes, everyone tells that one story.... The last jerk that ran the red light, or someone in a car that threatened them or crowded them.... Getting the focus of the discussion off of those vignettes and into the broader sphere of civility is really the challenge."

That's why, at the bike safety campaign meeting in August, she urged officials to use language such as "people who ride bikes" and "people who drive cars," as opposed to cyclists and drivers, which she says poses a false dichotomy.

Based on the fact that motorists are at fault slightly over 50 percent of the time, at least according to the DPD report, it seems difficult to reach any sweeping conclusion about responsibility in these collision. Indeed, it's plausible that there is a fairly even split when assessing which parties are breaking the law in a bike-vehicle crash. Likewise, the cause of crashes are probably more nuanced than the way that they are reported through DPD.

Regardless, the crashes are happening. The report says that there have been 163 accidents this year through August 23. And in June, there were 45 accidents compared to an average of 27 in years prior -- and in May, there were 37 accidents compared to an average of twenty over the previous ten years. In all likelihood, many collisions also go unreported, since the parties aren't likely to file official reports if they aren't badly injured.

Bike advocates also frequently point to studies showing that in general, an increase in the number of cyclists on the road usually leads to a decrease in per capita crashes, because cyclists have a stronger presence and drivers are more aware of them and the need to share the road. And the number of cyclists in Denver and especially in downtown is rising dramatically.

Another useful way to look at the rise in collisions is to examine changes in violations being given out -- and the DPD report has some helpful stats in this area.

As we wrote in our feature, the number of bike violations involved in an accident has grown dramatically: In 2007, there were 53 total violations, with the total rising to 88 in 2010 and 116 in 2011. This year through June, there have already been 82 violations associated with accidents. (There can be more than one violation per accident.) Bike fatalities are still relatively rare in Denver. According to data going back to 2004, the city has averaged 1.6 bike fatalities a year. There were two in 2010, one in 2011, and one so far in 2012.

A few specific violations have consistently dominated over the last ten years.

"Bicycles subject to traffic laws" is generally the most common violation given out after an accident -- with 58 total in 2011 and 41 this year through August. "Riding on the sidewalk" is the second most common, with 41 violations last year and 25 this year through August.

Bike safety advocates point out that the sidewalk can actually be one of the most dangerous places for a cyclist to be, because drivers aren't expecting bikes -- moving at a much faster pace than pedestrians -- to enter traffic from the sidewalk. This can be especially dangerous if cars are crossing the sidewalk when leaving lots or alleys, for example.

The rest of the violations given out after accidents (such as lacking a light at night or not yielding right of way) constitute such a small number that it's difficult to draw any conclusions about what behaviors are causing the crashes.

Continue for more on the most common violations and commentary from the Department of Safety. For all violations in general -- not just the ones given out after an accident -- the same categories dominate, with a few additions. Two other common violations include biking on the 16th Street Mall (which is not allowed, except on Sundays) and riding in marked cycling-prohibited areas.

Other miscellaneous data findings: Using the ten-year average, the number of collisions generally has peaked in the late afternoon, Tuesday was overall the most common day for accidents, and June, July and August have generally been the busiest months for collisions.

Bike safety in general is a concern at various levels in the city.

Daelene Mix, director of communications for the city's Department of Safety, says: "As a city, we have a civic responsibility to protect our citizens. Coming from the Department of Safety, that's a priority...making everyone feel safe to live, work and play in the city.... When we notice a trend...an increase in accidents, we have an obligation to get the right minds in the room and collectively come up with a plan to increase awareness."

She adds that she does not want safety concerns to discourage biking, which has increasingly become an important part of transportation here and a factor that makes Denver special.

"Working downtown, you see it -- the bicycle facilities that we have. That's not something that you see all across the nation. That's something that's unique to active cities," says Mix, who used to work in Denver's Public Works Department, which oversees bike infrastructure. "I see the bicyclists. I see the pedestrians.... To me, that is Denver."

Continue for the full report. Auto Bicycle Accidents

More from our Colorado Crimes archive: "James Holmes case: Defense drops sanction request over strange second mug shot"

Follow Sam Levin on Twitter at @SamTLevin. E-mail the author at [email protected].