There is no doubt about it. From my own experience.
I drove black toyota celica, a sport looking car, and notice - BLACK...
they just loved to stop me, sort of white (good) police cruiser, caught a black bad guy...
In one year of owning that car, I was pulled over more than 30 times.
Now that I drive white (family) sedan, I have not been pulled over even once - 6 months of driving.