California Code, VEH 21717.
https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?sectionNum=21717.&lawCode=VEH

"Whenever it is necessary for the driver of a motor vehicle to cross a bicycle lane that is adjacent to his lane of travel to make a turn, the driver shall drive the motor vehicle into the bicycle lane prior to making the turn and shall make the turn pursuant to Section 22100."