Believe me... they can pull you over for WHATEVER they want.
I've had cops pull me over and use a tint meter, measure the clearance of my front bumper and put a decibel meter in my exhaust.
I even had a cop who pulled me over in my GSX to ask what my gauges on the a-pillar were for. I explained they were Boost, Air Pressure and Exhaust temp. but he just wouldn't believe me and asked me to open my trunk to make sure my 'nitrous' was unhooked.
I'm sorry, but FUCK the police.