he doesnt have to use red on the rear tire...I have yet to hear of a state that has a different law..but all the one I've read was white or yellow (amber) reflectors on the wheels...so by that logic...white or yellow (amber) lights. Red is for the back only....that cop was prolly a bit green imo.
I believe in CA the law requires white or amber in the front and white or red in the rear.