This kind of thing is why we don't do adventurism. The shooter decided, without talking to anyone, that it was time to start shooting. Now PSL has an unexpected PR battle, and possible investigation, dropped on them without warning. Where is the strategy in that? How does this help PSL or the rest of us win the class war?
It's not even really about being on our best behavior or good PR, it's about practicality. Feds will come for the orgs eventually. But this kind of shit does not combat it in any way.