This is my personal take, but this is similar to an old philosophical argument. Can you use the Masters tools to dismantle the Master’s house? The master’s house in this argument represents systems of oppression/sanctioned violence and the tools are, well the tools. Hope I don’t have to explain that part. Anyway, my personal take is yes you can. You can not use the Master’s tools to build your own house.

In so far as the panel, dude was fine to shoot him. He just has to put the gun down and accept the responsibility of whatever his action causes.