Many years ago I was on my commute back to my home in West London. I was in a business suit, and carrying my everyday briefcase. I used the London underground, which connected to an overline railway for the last part of the journey. To get to the overline from the underground, there was a long escalator up and then a bit of a walk through a dark badly lit tunnel to the steps leading to fresh air. Actually, this was Vauxhall Bridge station. While I was standing on the upbound escalator, there was a bit of a commotion and two men rushed past me – one chasing the other and shouting – and it was apparent that the guy following had had his wallet stolen by the thief in front. Anyway, I did not do anything right away, but when I got to the top of the escalator, I could see that the two men were having a struggle, and it appeared that the thief was winning. So as I passed by, I asked the apparent victim if he needed any help: I was told to “f” off by the thief, and the victim did not answer, so I carried on. There was a second man in the tunnel who I think knew the thief – the tunnel was used by a lot of dropouts as a shelter – and he decided to chase after me. As he closed in behind me, I knew that a kick or blow was coming, so turned round at the last moment, used my briefcase as a shield, and threw a right hand punch which connected with this guy’s chin and knocked him out cold. I looked back at the other fight, which had stopped, and then walked on to the main station. leaving my assailant flat on the floor. Moral of the story – I did not know how badly hurt the man was and spent the next few days anxiously watching the local news for any reports!