CA Gov't Code Section 20252

If benefits are payable under this part because of an injury to or the death of a member and the injury or death is the proximate consequence of the act of a person other than his or her employer (the state or the employing contracting agency), the board may on behalf of this system recover from that person an amount that is the lesser of the following:

(1)

An amount that is equal to one-half of the actuarial equivalent of the benefits for which this system is liable because of such injury or death.

(2)

An amount that is equal to one-half of the remaining balance of the amount recovered after allowance of that amount that the employer or its insurance carrier have paid or become obligated to pay.