California Assembly Vote Brings State Closer to Formally Authorized Lane Splitting

California is on track to become the first state to formally recognize lane splitting as a legal maneuver for motorcyclists. Assembly Bill 51, sponsored by Assembly members Bill Quirk and Tom Lackey, authorizes the California Highway Patrol to devise educational guidelines for splitting lanes “in a manner that would ensure the safety of the motorcyclist, drivers and passengers.”

The bill passed the Assembly 74-0 on Aug. 3, with six Assembly members not voting. The state Senate had earlier passed the bill 38-0. Gov. Jerry Brown is expected to the sign the bill when it reaches his desk.

A.B. 51 defines lane splitting as “driving a motorcycle that has two wheels in contact with the ground between rows of stopped or moving vehicles in the same lane.”

The bill also requires the California Highway Patrol to consult with other agencies and organizations with an interest in road safety and motorcyclist behavior in developing the guidelines for responsible lane splitting.

Two state-sponsored studies conducted by the University of California Berkeley concluded that lane splitting is a relatively safe maneuver when both the motorcyclist and nearby drivers know the law and adhere to “safe and prudent” practices.

Lane-splitting riders were less likely to be rear-ended by another vehicle than were other motorcyclists, according to the studies. And lane-splitting motorcyclists involved in crashes were notably less likely than other motorcyclists in crashes to suffer head injury, torso injury or fatal injury than other motorcyclists.

The studies also found that there was no meaningful increase in injuries until traffic speed exceeded 50 mph and that speed differentials between lane-splitting motorcyclists and other traffic were not associated with changes in injury occurrence until the differential exceeded 15 mph.

Those findings closely align with lane-splitting guidelines posted on the California Highway Patrol website in 2013 and removed in 2014 after a complaint from one Sacramento resident, who argued that the Highway Patrol was, in effect, making law.

California is the only U.S. state where lane splitting is permitted. Current state law neither prohibits nor specifically allows the maneuver.

The Sturgis Motorcycle Museum and Hall of Fame recently named Marilyn Stemp and Steve Piehl to its board of directors.

Stemp is a pioneering figure in the motorcycle industry, founding IronWorks Magazine with her late husband, Dennis, and becoming the first female editor of a nationally circulated, mainstream motorcycle magazine. She also revived their trade magazine, Iron Trader News; edits the monthly Kiwi Indian News; contributes to several powersports media outlets; and is the founding editor of Sturgis Rider Daily. Stemp is a noted editor and writer of several motorcycle-focused books. Her consistent support for charitable efforts in the industry include the annual Biker Belles Celebration, Las Vegas BikeFest and as campaign chair for the Sturgis Motorcycle Museum’s development plan in 2014. She co-founded the Flying Piston charity events taking place in Daytona and Sturgis each year and is a National Ambassador for All Kids Bike. Stemp was inducted into both the Las Vegas Motorcycle Hall of Fame and the Sturgis Museum's Hall of Fame in 2018, and in 2022 she was recognized as one of the Top 100 Women in Powersports by DealerNews.