Brutally Honest: When is it OK to leave your teen home alone overnight?

I can't remember exactly how old I was when my mom went away for a night and left my older sister and me home alone. What I remember clearly though is the "talking to" I received when my mom returned and learned from our next-door neighbor that my sister and I had a party, which involved alcohol. "I'm so disappointed in you," my mother

would say over and over again, which were crushing words for a perfectionist straight-A student, who vowed never to let that happen again.

And it didn't. But the story illustrates two challenges for parents: 1) What age is OK to leave your teens home alone overnight? and 2) What if something goes wrong when you do?