California Code, Vehicle Code - VEH § 24404

(a) A motor vehicle may be equipped with not to exceed two white spotlamps, which shall not be used in substitution of headlamps.

(b) No spotlamp shall be equipped with any lamp source exceeding 32 standard candlepower or 30 watts nor project any glaring light into the eyes of an approaching driver.

(c) Every spotlamp shall be so directed when in use:  That no portion of the main substantially parallel beam of light will strike the roadway to the left of the prolongation of the left side line of the vehicle.

That the top of the beam will not strike the roadway at a distance in excess of 300 feet from the vehicle.

(d) This section does not apply to spotlamps on authorized emergency vehicles.

(e) No spotlamp when in use shall be directed so as to illuminate any other moving vehicle.