THX 138 said:
I don't think they can pull you over for it but get it as a secondary violation like tint or if you get a parking ticked they'll add it on.
From the California DMV website:
Front License Plate Bracket
11713.17. (a) Following the retail sale or lease of a motor vehicle for which the department issues two license plates, a dealer may not deliver the motor vehicle unless either of the following occurs:
(1) The motor vehicle is equipped with a bracket or other means of securing a front license plate.
(2) The dealer obtains a signed written acknowledgment from the person taking delivery of the motor vehicle acknowledging both of the following:
(A) The person expressly refused installation of a bracket or other means of securing the front license plate.
(B) The person understands that California law requires a license plate to be displayed from and securely fastened to the front of the motor vehicle and that the hardware necessary to securely fasten the front plate is available from the dealer.
(b) A manufacturer or distributor may not sell or distribute in this state a new motor vehicle for which the department issues two license plates, unless that motor vehicle is equipped or provided with a bracket or other means of securing the license plates.
Added Sec. 1, Ch. 365, Stats. 2004. Effective January 1, 2005.
~~~~~~~~
Display of License Plates
5200. (a) When two license plates are issued by the department for use upon a vehicle, they shall be attached to the vehicle for which they were issued, one in the front and the other in the rear.
~~~~~~~~
Some information on the CHP website indicates a missing front license plate is among the most commonly-written offenses among "hot rodders," but I'll speculate it's still pretty low on the list of sole reasons to pull one over.
Maybe someone from the law community will chime in.