There are many cases in sports where accidents cause unintentional injury. Two good examples:

1) What happens when you get hit in the head by a 95 MPH fastball?

2) The Felipe Massa crash at the Hungarian Grand Prix

We try to prevent these accidents as best we can. Batters wear helmets. Cars are improved with new safety devices, and so on.

But then there are the injuries caused by violence, where players ruthlessly and willfully attact others with the intent to cause injury. One example from a couple of months ago comes to mind:

A huge hockey hit leads to a concussion

And then there is this story/video, where a female soccer player named Elizabeth Lambert is clearly out of control and savaging other players on the field:

VIDEO: Watch Elizabeth Lambert, The Dirtiest Player In Women’s Soccer

I do not know the answer to this question: Why do human beings allow this kind of violence? Nothing is gained from it. Truly talented athletes are rare, and allowing them to be injured by rogue players takes them out of the game, and therefore diminishes the game for everyone. Why aren’t violent players immediately and permanently suspended from the sport? In the case of Elizabeth Lambert, why hasn’t she been arrested and put in jail?