Cal. Gov. Code § 50872

Upon the written request of a member who becomes physically disabled by reason of bodily injury received in the performance of his duty, the board may retire him and order that he be paid from the fund, during his lifetime, an annual pension equal to one-half of the annual salary attached to the rank he held at the date of retirement. If the board deems it for the good of the department, it may take such action without request by the member.