California Code, Vehicle Code - VEH § 26710

(a) It is unlawful to operate any motor vehicle upon a highway when the windshield or rear window is in such a defective condition as to impair the driver's vision either to the front or rear.

(b) Notwithstanding subdivision (a), it is unlawful to operate any motor vehicle described in Section 34500 upon a highway when the condition of the windshield is other than described in Section 393.60(c) of Title 49 of the Code of Federal Regulations.

(c) In the event any windshield or rear window fails to comply with this code the officer making the inspection shall direct the driver to make the windshield and rear window conform to the requirements of this code within 48 hours. The officer may also arrest the driver and give them notice to appear and further require the driver or the owner of the vehicle to produce in court satisfactory evidence that the windshield or rear window has been made to conform to the requirements of this code.