There are many causes why people go into violence. If we talk about sports we also talk about competitiveness. People, or teams, get sometimes extremely competitive because of the ultimate goal to win. Quite often players get so angry because they cannot make a play, because somebody from the other team fault on him without the official noticing it. These are just few of the causes that can lead to violence on the field, or court. As a solution to these actions they invited rules. Rules that the judges, officials, are able to supervise. In case of violating one, with such a cause as violence, the players, or worse, the whole team, can get suspended from the game, or even from the whole season.
There is violence not only on the field, but as well in the audience. There are people who tend to create conflict on the basis of different opinions. Imagine a situation when somebody sitting next to you is yelling at the players, distracting you from the game, making the whole situation uncomfortably awkward. You stand up and let that annoying person know that he should stop. He gets aggressive, and begins to attack you. Violence is right there. If you are lucky, then comes the security and helps you. Well, not in all cases. Sometimes you can get even seriously injured. Now the question, how can you prevent this from happening? However much I try to figure out the solution I cannot think of anything. People are people, you cannot sit them down and have them take a personality test before they enter the stadium. You just have to trust in their good, and maybe a security would be a good help to have available to the public too.