So if you are caught sexing up a dossier on a foreign tyrant's ability to fire chemical weapons at British bases and it leads to lots of deaths and billions of pounds spent firing depleted uranium munitions at civilians who are left with a legacy of radiation-related birth defects, it's best to own up.
If you try to pay off a prostitute over your use of her services by sending a mate to meet her at the train station with an envelope stuffed full of cash and a tabloid newspaper is photographing the whole thing and that mate later admits you made him do it and a diary proves you perjured yourself at the original trial, just plead guilty and get it over with.
If the nation's beef trade is on its knees because of new medical claims about Mad Cow Disease the thing to do, as agriculture minister, is not to force-feed your own uncomprehending child a burger on national TV.
But then some twats never learn.
Which is the reason why, I imagine, the Committee on Members' Expenses - not a Soho sex trade price-setting body but a group of politicians considering their own fraudulent colleagues - has suggested that MPs stop bothering submitting a receipt along with their claims for reimbursement from the taxpayer.
Why should they? Why should 650 people already paid a basic rate of £65,738 a year with access to a publicly-subsidised bar and restaurants possibly have to explain why they want more out of us? Why shouldn't they scrutinise their own expenses, why do they have to prove they actually spent the money, why can't they reduce the amount of time they spend ordering their taxpayer-paid secretaries who are usually their wives filling in forms?
Why shouldn't they get their wisteria pruned, their bellies filled, their Grade-II listed homes repainted, their moats cleared, their tennis courts relaid, an expensive armchair for their botties to rest in and a Bang and Olufsen giant flatscreen telly?
Just because every other employee in the country - including journalists, since you're asking - has to provide receipts and explanations for their spending why on earth should public servants have to do the same? Poor sods. They have such a hard life, don't they? With staff and offices and homes they can furnish and flog for a profit without spending a single penny of their own, with those long Friday afternoons spent listening to other people's problems and that horrid half-hour on Wednesdays where they have to sit in an historic palace to shout at the boys from the other team.
What right do we have to expect anything of them?
BECAUSE THEY ARE PRINTING MONEY, AND IT'S OUR BLOODY MONEY, THAT'S WHY.
Some pigs are more equal than others, hey?