Fighting and others opinion toward you.

Hello my peoples,

Fighting someone isnt always necessary,but sometimes it is hard to avoid.Now lets say that you witness someone you knew,not really close to them,but you knew them,beat someone else up.How would you respond to that person?

Now lets say that a friend of yours beats someone up.would you opinion of them shift?

Finally,How do you think the opinion of others toward you would change if you beat someone up?

Well,thanks for reading,and please comment!

Stay Awesome