The police who raided and smashed the crap out of a building full of peaceful protestors in Genoa in 2001 will get off completely from all their crimes, despite being found guilty. A statute of limitations means their convictions and sentences will expire before going into effect.
This kind of injustice will breed violence. I wouldn't be at all surprised if the victims decided to mete out their own justice, given the system has completely failed them. What's more, I imagine if the cops ever tried to raid a building full of protestors again, the protesters might decide to use violence to defend themselves, since the state won't do it for them.