Mass arrests on the Brooklyn Bridge are a good way for a protest campaign to break into mainstream media nationally.  Although Occupy Wall Street got some coverage in national outlets over the past two weeks, international news provided more extensive coverage.  Of course, movement sites, blogs, and Twitter provided even more coverage.

But upwards of 700 arrests near a national landmark is newsworthy everywhere.

And here’s the dilemma for activists: conflict, drama, celebrities, and novelty make news.  Alas, it generally doesn’t make for coverage of issues, and the things demonstrators do to get noticed may not bring them the kind of attention they want; they may look foolish, provocative, or deviant.  But polite, informed discussion of important issues by regular people isn’t so interesting to cover.

In one way, the New York Police Department’s mass arrest did the emerging Occupy movement a favor.

So, who was responsible?

The New York Times City room blog posted official police videos which clearly show police with megaphones warning demonstrators that failure to clear the traffic lanes will lead to arrest.

But it’s also very easy to find other videos on line that show police officers appearing to lead demonstrators into the roadway.

Watch a few videos and you’ll probably conclude, as I did, that police warned demonstrators and that many demonstrators thought they were following a safe demonstration route and received no warning of impending arrests.

These days, most large demonstrations are negotiated, even choreographed, in advance by the organizers and the police.  They permit locations, arrange for sound, and even identify zones where protesters can be arrested.  The leaderless Occupy Wall Street group hasn’t been negotiating with the police, and the open source ethos has allowed many competing messages to flourish within the ranks of the protesters.

This means less predictability–and more risk–for everyone involved.