I'm proud to say that I am in the 20% of people who do NOT stand by. I have had 2 opportunities to intervene when I saw children being physically abused. One was a mother beating her 6 year old child for picking up a ball...he wasn't throwing it, kicking it, knocking stuff off the shelves (I work retail). I could hear her from the back of the store and went to her and told her not to strike that child again or I would call the police. She started to argue with me. I said "He's just a little boy". She called my corporate office and my boss came in to reprimand me. I told my boss if she expected me to sit back and just watch that, she may as well go ahead and fire me, because I would always step in to protect a child.
The 2nd time I came upon a mother beating her 9 year old boy with a stick. It was the most sickening noise, because I heard them before I saw them. I told her to stop it, and called 911 on my cell phone. She actually told me "He came out of my body, and I can do anything I want with him." I told her "Shame on you. God gave this child to you". She ended up being arrested and I had to go to court to testify against her. Part of her defense was "who was I to be sticking my nose in her business." I am a mandated reporter (as is Joe Paterno) and I told her I would never stand by. The judge thanked me and said that he wished more people would step in to help a child in distress.
Where do I get my nerve to do this you might ask? I'm not very big, or very young, or very strong. But I was a child who was beaten. I always prayed someone would rescue me. Now I am the rescuer. And I promise you, if I had witnessed Jerry Sandusky abusing that poor boy, I would not have walked away. I would have kicked his butt, and rendered him unable for that part of his anatomy to EVER function again.