A progressive "good guy with a gun" stopped a right-wing gunman who attacked volunteers supporting a protest. When official thugs came, they didn't believe the survivors' report and arrested the good guy.

It's very rare that a "good guy with a gun" is present when someone starts committing murder. In this case, his presence was not a matter of luck. He was there to protect people at the protest. The protest organizers realized in advance that the violent tone of right-wing hatred might inspire someone to shoot protesters, and wisely arranged to have some guards.

This one even managed to disable the killer without killing him, so he will face trial.