Yeesh, how hard is it to keep it contained? No non-student 'protestors' on campus, no training of 'protesters' on campus. Any convictions of students for 'protest' violence means expulsion. No overnight encampments, all 'protests' must end at a reasonable hour. Any violence or threats, the 'protest' gets shut down and instigators taken to jail, so on and so forth.
This is not a method problem, it's a a political will problem.