Tweeting Police Activity

The Pittsburgh Post-Gazette reports this morning that police have arrested two men for Tweeting police movements during the recent G-20 summit in Pittsburgh.

According to the paper, the two listened to communications on police and EMS scanners and Tweeted at least some of what they heard, presumably to activists and protesters in Pittsburgh. “They are accused of hindering apprehension, criminal use of communication facility and possessing instruments of crime.”

The ACLU is on the case. The Post-Gazette story includes a number of quotations from an interview with my Pitt criminal law colleague John Burkoff.

The story has a “terra incognita” feel to it, but I wonder whether that’s appropriate.  (As an aside, I wonder:  If you’re Tweeting, then is your laptop or mobile an “instrument of crime”?  Or is the software the “instrument of crime”?)   The First Amendment argument here seems pretty compelling to me.   Perhaps I’m missing something.