David Cameron says he wanted to give Andy Coulson a second chance. When I was about 12 I remember my father driving me to school and telling me never to give anyone a second chance. I protested. He explained he didn't mean don't give them a second chance when someone had made an honest mistake - people make mistakes everyday. But if someone is lazy, the chances are they will always be lazy. If they are unreliable, it will be hard to trust them again. If they make a habit of lying, you will always have to be careful. I didn't agree with him. And when I started running the BSC I was always ready to give someone a second chance. In fact I've done it many times. It has never worked.