The California Assembly has approved a controversial bill to sanction and regulate lane-splitting by motorcyclists.

California would be the first state to officially legalize the practice, which is already widely tolerated by state law enforcement officials.

The bill will now go to the Senate, where it also has broad support. The Assembly bill passed Thursday morning on a 58-14 vote.

It was co-authored by Bill Quirk (D-Hayward), Tom Lackey (R-Palmdale), a former California Highway Patrol officer, and Kansen Chu (D-San Jose), who became interested in the topic after a staffer’s nephew was killed while lane-splitting at high speed.


Under the terms of the proposed legislation, motorcycles would be allowed to travel between cars at speeds up to 15 mph faster than the flow of traffic up to an overall speed of 50 mph.

Those numbers were based in part upon a UC Berkeley study by long time motorcycle safety researcher Thomas Rice, which is expected to be published shortly.

Lane-splitting -- beloved by traffic-beating bikers but detested by many automobile drivers -- is common in many European countries but generally outlawed in the U.S.

Its legality has been murky in California, however.


Neither explicitly legal nor illegal, lane-sharing or lane-filtering until recently had the tacit approval of the California Highway Patrol and California Department of Motor Vehicles. Both agencies published guidelines for safe lane-splitting until last year, when they pulled them in response to lane-splitting critics.

Though many automobile drivers and some motorcycle riders view the practice as unsafe, studies have shown the opposite -- that motorcyclists on freeways are less likely to be involved in accidents while splitting lanes than they are while sitting in stop-and-go traffic.

In traffic, where bikers may be less visible to other motorists, they are more vulnerable to potentially serious rear-end accidents.

Reacting to news of the pending vote, Los Angeles Times readers continued to argue over the safety and fairness of the practice.


“I’m an avid motorcyclist who used to live in France, and can’t imagine motorcycling without splitting lanes,” wrote one.

“How about a law like this being submitted to a general election, and let the everyday drivers state their position on this law?” asked another, who complained that lane-splitting would “promote the motorcyclist rights for hogging the highways.”

California may be the first state, but not the last, to pass such a law. Washington, Oregon, Nevada, Texas and Tennessee have all considered or are now considering similar legislation.

Twitter: @misterfleming