Police have arrested another suspected rogue trader at a big investment bank, a man named Kweku Adoboli who is alleged to have lost $2 billion for UBS in unauthorized deals.

A story about Adoboli in the Wall Street Journal describes him a “well educated” and “polite,” which must fall into the category of Dog Bites Man.

After all, has anyone who looked and acted like a Hell’s Angel ever held a job for very long at a big bank?

If Adoboli is guilty, his name will go alongside lots of white-collar criminals who seemed perfectly nice, smooth and well turned out, with all the right degrees after their names.

UBS may have done proper due diligence on Adoboli before hiring him and may well have turned up no red flags.

But the lesson here for anyone doing due diligence is that a nice suit and a good degree mean a little something, but not enough on which to make a decision about a person’s character or ability.