Not murder if the killing was unintended. In truth, I'm disinclined to shame anyone but the people in front who deliberately broke the doors.

Here's the thing: If you're in a crowd and you see someone getting trampled, you may want to help the person, but you're also aware that the same thing could happen to you if you stop to do so. And then you'll have helped nobody. It's a reasonable fear of the frenzied, unknowingly violent people behind you that propels you forward.

The trick, then, is not to be in the crowd in the first place.