I think it's mislabelling to call this kind of thing "PC" - it's a different game being played here.

"Zero tolerance" though it's an ugly term in itself, can make sense in certain situations, such as dealing with environmental damage by getting it cleaned up without delay. But when people try to use it as a way of dealing with behaviour in general, so that in place of an attempt to reach a just and appropriate solution there's an automatic mechanical application of a rule, regardless of circumstances - that just isn't the way to do it. Basically it's a Taliban way of thinking.

As I commented earlier, conceivably in the circumstances (which we don't really know, true enough) suspending this pupil might have been an appropriate thing to do, on the grounds of discipline and disruption and that kind of thing. But tying it into issues of threats to teachers and violence in schools - that's a nonsense. It sounds very much as if they may have rewritten the rule book so that disruption and insolence can't be reasons for punishment, and then they cast about for some way to get round that, by misapplying other restrictions that exist for quite other very serious reasons.