Actually.......I believe that a Bismarck attorney flipped off and said that to a Bismarck PD officer several years ago (or was it Mandan?) and was arrested for Disorderly Conduct, fought it to the ND Supreme Court, and it was overturned because Police Officers are held to a higher standard and should expect to hear things like that.
Had he done it to a regular person, it would've stuck.
Oh, by the way, my car was punched by an GFPD officer doing a very poor job of directing traffic outside the Alerus Center before a Sioux Football game this year. I feel sorry for someone that makes that guy mad.