If Person A violently attacks Person B, then Person B has a right to defend themselves on the legal theory that Person A instigated the violence. "Credible threat" clauses muddy the line, but continue to rest on the pedestal of reaction versus action [1].

Here a court gave a company the right to instigate violence against the defendant. At least to this American, that's absurd.

[1] http://cji.edu/site/assets/files/1921/actionversusreaction.p...