NCPA - National Center for Policy Analysis

Bikes and Red Lights

December 7, 2011

It'll come as no surprise to cyclists -- not to mention irritated drivers -- that bike riders tend to have what we might kindly refer to as selective vision when it comes to stop signs and traffic signals.  Cyclists regularly run stop signs and signaled intersections when the coast is clear.  Momentum is key for the bike rider and coming to a complete stop when nobody's around is hard to justify.  But even so, there's an inherent risk in not obeying traffic laws, says Nate Berg of Atlantic Cities.

A recent study by Portland State students monitored intersections around campus to see how well drivers and cyclists adhered to red lights.

  • The report shows that of the 497 cars observed only 36 ran red lights, while 58 of the 99 bicycles observed blew right through.
  • That's about 7 percent of cars compared to 58 percent of bicycles.
  • Two of the three intersections the students chose to study have a cycle track, or a bicycle lane separated from traffic lanes.
  • The researchers found that cyclists were more likely to run red lights at the intersections with the cycle track, with about 70 percent of riders running lights compared to less than 40 percent on the shared street intersection.

While it's not likely that cyclists will begin to comply fully with the laws of the road, this study does shed some more light on the potential dangers of the road.  More pedestrians are put in danger when other users of the road ignore the rules.  And though bike-person accidents aren't incredibly widespread, they do happen.  Even more concerning should be the increasing potential of car-bike accidents that can occur when stop lights are ignored.

Source: Nate Berg, "The Uncomfortable Relationship between Bikes and Red Lights," Atlantic Cities, December 2, 2011.  Aaron Cole et al., "Red Light Behavior between Motor Vehicles and Bicycles," Portland State University, November 28, 2011.

For text:

For study:


Browse more articles on Government Issues