I’m temperamentally suspicious of the British press when it’s in self-righteous mode — as it is currently about MPs’ expenses. (I’m with Macaulay on that one. “We know no spectacle so ridiculous”, he wrote, “as the British public in one of its periodical fits of morality”.) And I suspect that behind at least some of the apparently outrageous claims there is probably a sensible explanation.

But the thing that really bugs me is the incessant invocation of the mantra that any expense claimed, no matter how bizarre, was “within the rules”. We had the same thing a while back when a very senior Irish bank executive was shamed into resigning when it was revealed that he had been ‘warehousing’ huge personal loans for nearly a decade to keep them off his bank’s balance sheet at the end of each financial year. As he crashed in flames, he issued a statement saying that while his actions may have been ‘inappropriate’, nevertheless they were within the law.

What was missing in his case — and is clearly missing in some British MPs — is any sense of honourable behaviour. His actions were clearly designed to keep the truth of his financial dealings with the bank he ran from being known. Most of us who are lucky enough to be in employment are entitled to claim legitimate expenses. But most of us have a sense of what’s reasonable and what’s not. For example, if I go to London on university business it’s obviously reasonable to claim for any rail, tube and/or taxi fares needed to get me to and from my destination. But is it reasonable to claim for the Americano that I would have had anyway, travelling or not? Obviously not.

And the irony is that Parliamentary etiquette still insists that the shysters who have been exploiting the expenses system should be referred to as “Honourable Members”. Perhaps the best revenge would be to refer henceforth to the most blatant claimers as Dishonourable Members.

As ever, sunlight is the best disinfectant. When in doubt ask yourself: How would this look if it were presented in evidence in court? Or published in the report of a committee of inquiry? And then decide what to do.