I live downtown, I've rode by bunches of cops with my D&D's and never got so much as a glance. In fact, I've never heard of anyone getting ticketed.
I remember speaking to one officer and him telling me that the law was for enforcement in select areas, i.e. neighborhoods where there were complaints. I was a little worried because my friendly local HA clubhouse is six blocks from my house, and I figured the police would be much more willing to pick on me than a platoon of 1% er's, but so far, so good.