Seems like this sort of thing frequently happen at the G20. As such, this strikes me as a "beg forgiveness rather than ask permission" sort of tactic. I'm not sure how such travesties of abuse of power could occur time and time again, yet they always try to pull it off after the fact as something of an outlier. Which is really odd considering these sort of events illustrate how a police state could easily get out of hand against it's citizens. The folks in this chain of command should be relieved of duty, at the minimum, and fined heavily with some degree of consideration for such a lack of oversight.

If something like this happened in japan, all the involved public officials would've committed suicides.
It's a shame western society doesn't have such a high sense of responsibility and respect to one's position.