Governor Brown just signed into law Assembly Bill 51 which officially makes it legal for motorcycles to lane split. The new law gives the California Highway Patrol authority to develop guidelines with respect to absolute speed as well as speed relative to adjacent traffic. The CHP used to have guidelines of 50 mph absolute speed and a maximum 15 mph faster than adjacent traffic, but scuttled those guidelines a while ago. Awareness of the new law will hopefully increase safety for motorcyclists. In any case, the new law will undoubtedly affect determination of fault and liability in personal injury cases brought by motorcyclists injured while lane splitting, predominantly in favor of the motorcyclists.