It is purely up to personal choice if you want to have a go.
I wouldn't judge someone for not having a pop for fear about their own safety.
I wouldn't judge someone for having a go anyway.
Well done to the lady, her actions seemed to spur others into getting invoved, which in turn helped detain at least one of the scum.
Now for the judiciary to let them off with a pathetic sentence, and be back out to do it again in no time.
It's the lax judiciary on trial, not the people.