AFAIK in CA you can have the rear windows blocked out... Just the 'front 2' windows and windshield must remain unblocked.
Many people choose not to abide by it... When I lived in Yucca Valley/high desert, no cop would bat an eye at tinted windows.
I haven't seen any tickets for it down here in OC either, and there are plenty of SUVs and non-limo cars with full-dark tint front and rear.