The key moment in the criminal career of Frank Abagnale - the conman played by Leonardo DiCaprio in Catch Me if You Can - came when he saw the way a Pan Am pilot in uniform was treated. He obtained a uniform and a fake ID card and set to work. It proved much easier to get money, girls, food, free flights when wearing a uniform. Want to know how Madoff managed to ply his trade without being properly questioned? Want to know why the regulators didn't bring him to book? He was dressed in the city equivalent of a pilot's uniform. The authority of his big company and his intimidating reputation clothed him.
But it was the maths that undid him. He chose the wrong con. Ponzi schemes collapse. It is almost mathematically impossible for them to keep going for ever. They are, incidentally, a particular feature of rising markets and come unstuck in downturns. Not all cons come unstuck like this. The mark doesn't like to be thought an idiot or greedy or a crook. So they often keep quiet or even side with the con artist. Even Ponzi himself kept some of his fans. I bet Madoff does too.