Earlier quoted context omitted.
That looks very suspicious, but if this were really a widespread technique by the police, I'm assuming there would be more than a single video taken. I mean, we know the black bloc and similar groups engages in these tactics, they've been doing it since Seattle WTO 1999. I've seen it in person to protests I've been to (as a protester). It's very hard for me to believe that all of a sudden those people are no longer a…
> we know the black bloc and similar groups engages in these tactics How do you know this? What's the process by which you established this as a known thing?
Primary, by power of observation. But OK, I'll make this as vague and 100% foolproof as I can, to start: there are people who dress in black, and masks, and destroy stuff and commit violence at protests. That's from actual observation. It's not just 1-2, there are groups of them. That's my personal observation from being at 2 protests with such groups.
Now, combine that with all the sources references in this Wikipedia article: https://en.wikipedia.org/wiki/Black_bloc
Along with many, many, many dozens of media reports like this one: https://www.youtube.com/watch?v=Mr0i6piW_ak
I'm able to discern a certain pattern.