I'm 100% in favor of the protestors' cause, but if you want probable cause, burning down a police station, housing unit, and nearby businesses certainly qualifies.

And what about all the other people caught in the dragnet? Most of whom presumably did nothing. These people have no idea if they are also being surveilled. I mean, who knows what else the government is doing "while they're there."

There are smaller aerial drones that could be used, which would capture the same relevant footage, without the potentially miles-wide dragnet. That's my main objection here: innocent people shouldn't have to give up their rights because the government can justify it. A good justice system would do their best get the minimum amount of information necessary, in order to protect the innocent.