California commuters now have an answer to the practice of lane splitting after Governor Jerry Brown signed legislation making the practice legal. Assembly Bill 51 passed unopposed with a vote of 69-0 and will go into effect January 1, 2017.
Lane splitting, the practice of motorcyclists to “split” the lane between stopped or slow moving vehicles was not previously defined by state law.
The legislation does little more than authorize the practice. It is now up to the California Highway Patrol (CHP) to create guidelines for implementation.
The CHP previously published guidelines on lane splitting in 2013, but was challenged by a state employee. The employee complaint questioned the legal authority of the CHP to create guidelines for something not defined as “legal” by California law. At the time, there was simply nothing in the law, for or against. As a result, CHP removed the guidelines from their website.
The bill requires CHP to work with the Department of Motor Vehicles, Department of Transportation, the Office of Traffic Safety, and a motorcycle organization focused on rider safety.
Though never defined by California law, lane splitting, also known as “filtering” or “lane sharing,” has been practiced by motorcyclists on California roadways for years.
Proponents of lane splitting have maintained that it protects riders. Motorcyclists face a visibility problem as the slim profile of bike and rider can make it hard for motorists to recognize. That lack of recognition makes motorcyclists vulnerable in stopped traffic according to proponents. And where a simple fender bender between two automobiles typically means drivers walk away, the same collision between an auto and bike can mean death for the rider.
According to the National Highway Traffic Safety Administration (NHTSA), upwards of 40 percent of all car accidents are rear end collisions. Proponents contend by moving motorcycles outside the normal path of traffic, it lessens the likelihood of a rear end collisions and more serious accidents.
And they might have some science on their side.
Steve Guderian, a motorcycle safety consultant and former California Motorcycle Patrolman notes that corresponding surveys done in California in the late 70s, one in Europe, and the most recent UC Berkley study all point to the same conclusion. That lane sharing saves lives.
The UC Berkley study, done by the Safe Transportation and Research Center (SafeTREC) in 2014 found that riders suffered less serious injuries when the accident occurred during the practice of lane splitting. These riders had less head and fatal injuries when involved in an accident. The study involved accident reports on 900 motorcycle accidents.
The study found that when riders maintained no more than a 15 MPH speed differential with slower traffic, accidents were less likely and less fatal. At slower speeds bikers have more time to react with better lines of sight. Lane splitters tend to be weekday riders, riding at commute times with better helmets, and riding at slower than average speeds.
Traffic Congestion & Environmental Factors
Some supporters argue that there are environmental benefits to lane splitting.
For instance, when a biker splits lanes they remove themselves from the queue of vehicles backed up in the line of traffic. This means shorter lines of traffic, which in turn means increased mobility. When vehicles spend more time moving than waiting in traffic it means they are off the roadways sooner, burning less fuel and creating fewer emissions.
A 2012 Belgium study bears this out noting there would be fewer emissions because vehicles were not stuck in traffic jams as long.
Lane splitters will continue doing what they do until the California Highway Patrol establishes hard guidelines to regulate lane splitting behavior. Most believe this will involve a maximum general traffic speed threshold that lane splitting can be done and a maximum speed that riders can travel between lanes.
One thing is clear, motorists, in spite of many seeing lane splitting as a dangerous practice, will need to adapt to motorcycles traveling near the center line. The new guidelines should bring clarity for all California commuters.
But will the oft quoted saying “as California goes, so goes the Nation” be the case with lane splitting for other states? For most states, that answer is a clear “no.”