There is a lot of discussion of how, and when, churches might be considered violated/in need of reconsecration in Catholic canon law; violence as well as murder is considered (as is adultery, and material destruction). Gratian's Decretum is one of the standard references; it states that after an act of violence a church should be cleansed and reconsecrated. People then get into all sorts of debate as to what counts as violence - murder does, but also deliberate bloodshed (but not, say, smacking your disobedient child so he has a massive nosebleed ...). There are services specifically for reconsecration after violence.
In the Church of England the situation was initially more vague, because the rite of consecration itself was a bit contested (the Protestant reformers tended to think it was a Catholic practice in and of itself). I don't honestly know what the situation would be today.
It will vary in other types of church too, I'd imagine.
If you had a process whereby you hadto re-consecrate it, surely then you’d be saying that the force of evil that was responsible for the act was stronger than God himself? That wouldn’t make sense at all. I’d have thought there’d to prayers for it, that’s all.
I don't think so. You also reconsecrate a church in the Catholic rite if it has been substantially and suddenly damaged (eg., burnt or hit by an earthquake or something). It's not about evil specifically, but about anything that disrupts the unified sanctity of the building.