An article in the Guardian states that the middle class cost Britain £14bn per year. The article is actually based on a survey done by two scientists at the University of Keele (not to be confused with the University of Kiel). Professor Susanne Karstedt and Stephen Farrell carried out a survey:

bq. They quizzed 4,000 people aged 25-65 in England and Wales and western Germany to see how many admitted white collar dishonesty. Germans outstripped the English and Welsh in all but one kind of crime: they were less likely to keep change given in error.

Statistics are given. Perhaps the Germans were just more honest?