I hate to tell you but background checks for people working with kids have been around long before Penn States situation. There are background checks before you can even perform construction work etc... in a school and you are not even working with the kids.
Your Sandusky reference in this thread should be in the dictionary under "reductio ad absurdum." What Sandusky did was already illegal. Dance is not even illegal in a baptist church.
My point was twofold: 1) Common sense went out the window with the Sandusky situation. So, relying on common sense doesn't always work. 2) Volunteers didn't need the background checks before Sandusky in PA. All that is new. The laws cracked down here because of one situation in which common sense went out the window.