There's always been OOC arguing. You should've seen some of the insults flying back and forth on Atamara 7-8 years ago during the war between Eston and Norland. Compared to that, this is nothing. And I don't care how toxic you think the League may be, anything said IC should not be taken OOC. If you feel personally insulted when your realm or character is being slandered IC, then you need to take a step back and remind yourself that you're playing a bunch of medieval nobles with long-standing rivalries and very opposite interests.
This doesn't have to be clear and obviously a player attack to be guilty, it just has to be clear and obviously NOT a player attack to be not-guilty.
I'd like the other Magistrates to correct me if I'm wrong, but this is NOT how cases are decided. This is NOT 'guilty until proven innocent' justice. That would set a very bad precedent and kick the door wide open for endless frivolous accusations.
