I do hope that he gets a swingeing order for costs and compensation from the Australian Federal Police, because, as it turns out, the prosecution was entirely misconceived and unfair. And it helped bring Slipper's glorious political career to an untimely end. And, to add insult to public injury, Slipper was replaced by Malcolm Brough. Even Tony Abbott, I am sure, would agree that the damages for that must be very great.

AFP detectives made the elementary mistake of assuming that the standards by which a politician could be convicted of "fraud" bore some relationship to the meaning of the word as commonly understood, whether by members of the public or even by specialised lawyers. Indeed, even the ACT chief magistrate made the same mistake as the police. That was in addition to the error of thinking that common sense could be applied when deciding whether taking hire cars for boozy tours and lunches around Canberra wineries could amount to conscious and witting overegging of the entitlement pudding. Likewise with some indications of concealment, misdescription of route and number of trips, and personal aggrandisement as some of evidence of a guilty mind or conscious wrongdoing on the part of the speaker.

Her Worship even made the mistake of inferring that the rules made some sort of distinction between being chauffeured around for public or private purposes, her duty being to decide, from the relevant facts and circumstances, which was what, the burden of proof of conscious diddling always being on the prosecution. What she failed to appreciate was any purpose was or could be a public purpose unless it was simply impossible. In any event, it turned out, a politician had only to say that it was a public purpose for the matter to be uncontrovertible.

How, anyway, could anyone, even a mere independent outsider, judge whether a trip to a winery was not educational, or for the purpose of briefing or being briefed by an adviser, or perhaps even a lobbyist?

The consequence is that we can criticise a politician for ill-judgment when she, or he, rorts the system - say by attending or returning from the wedding of some colleague or India maharajah. I am happy to call Slipper a rorter, perhaps even a witting one. But criticising him, or regarding his misjudgment of popular tolerance for political rorting, should not imply guilt of a criminal offence. It's just rorting - abuse of public office in the ordinary sense, rather than in a criminal sense.

If a politician decides, after popular criticism to return money, that is, generally, not to acknowledge criminal fraud, or an accident, but so as to forestall further public criticism.

It could be different, of course, if one were to claim for a trip, or perks, of which one had not actually availed oneself. That would be the most sheer and wicked imposition upon the state. Even then, however, prosecution is unlikely unless one has seriously offended the Minister for Finance, because there is an indulgence granted even to the most blatant rorting, provided that a mistake is claimed. All one has to do, under an arrangement formalised in Nick Minchin's time is to pay it back before the cops arrive at the door. Even if you don't there is not much chance of being prosecuted.

There is simply no limit to the entitlement of politicians. Or to their entitlement mentality. Or, at least, no limit imposed by law.

If one is too blatant, and there any number of protections in the system designed to make detection and exposure less, rather than more, likely, one might cop a lot of public criticism from poor mug voters who do not appreciate the life of simple public service of our representatives.

But criticism, however severe, is not the same as a spell in pokie or the sort of public disgrace which makes continuing public service difficult or constitutionally impossible. We put unemployed people in jail for making unjustified claims, but re-elect folk who draw more in mere travelling allowances in the typical fortnight than the average Australian pensioner couple.

Restraint with access to, or expenditure from, public funds, is for poor people, nor for representatives of the ruling classes.

I have little doubt that Justice John Burns, of the ACT Supreme Court, was entirely correct in his assessment of the Slipper slip-ups. The outcome is not Burns' fault.

Strange as it might seem the rules relating to the entitlements of politicians were made by politicians, and the coach horse-and-cart size loopholes were put there deliberately.

Those who think that the rules ought to be the same for politicians and pensioners should elect some politicians who agree. If you can find any.

There are independents and Greens who can affect private as well as public virtue, but any mainstream politician with an attack of public conscience has to live in fear of assassination from his, or her, more grasping colleagues, particularly in the Senate.

Department of Finance bureaucrats, who have to administer the rules, are well aware of the gaps, but hardly encouraged to do anything about it. Indeed, the last time, in about 1997, bureaucrats did draw attention to apparent breaches of the rules, if discreetly via the proper channels, the prime minister of the day became furious and abolished the department, and the jobs, of those involved.

When in Canberra a politician can claim for trips made on parliamentary business, a phrase deliberately nowhere defined, it seems definitely to include a trip to a restaurant or the pub for any purpose whatever. Moreover, the system was designed so that a payment is made and authorised simply on the presentation of a claim. No one checks unless, for some reason, someone from the ministry feel pressured to ask the department to have a check made. The department, usually, has no means to testing the assertion, sometimes only implied, that a trip, charged on a parliamentary credit card, was on parliamentary business.

Curiously, Slipper made an inquest into his travel more easy (once his old best friends decided he was now an enemy) because he did not usually pay with his entitlement card. Instead, he chose to break up big bills - in the hundreds of dollars - into several more modest and manageable sums, then filling in the claim by hand on to a Cabcharge form. Filling in a form involved filling in a stub explaining the trip, if by a sometimes spurious explanation such as "Parliament House-suburbs". In the normal case a politician making such claim with a card would not even have to make such an implicit representation of what, if anything, the trip was about.

Slipper had an explanation - quite unconvincing to me - for his breaking up single trips into multiple claims, but the mere fact that his story was questionable did not, of itself, prove him to be a liar or a fraud.

I should not like it to be thought that people go into politics with petty larceny in their hearts. Nor that they are necessarily overpaid, or even paid over-generously. Not a few make a financial sacrifice to be there, though the proportion of these, particularly on the Labor side of politics, is much lower than you might suppose from the claims to the contrary. But there are always a few, on both sides of politics, who have a rorting mentality. They include ministers, sometimes prime ministers.

I could nominate examples from either side of politics in recent times, but, for good taste shall refer instead to a diary sketch made about former Country Party leader Sir John "Black Jack" McEwen by his parliamentary colleague and friend, Sir Paul Hasluck, in the late 1960s.

"McEwen is a very selfish man, a man who wants to get his own way and will do almost anything to get it," Hasluck's profile, ultimately published in The Chance of Politics, said. "His selfishness led him into self-sacrifice. He expended himself beyond all reason in order to gain his own ends and get what he wanted.

"I hesitate to use the word 'avaricious' but it is hard to find another. Even in matters of personal expenditure, ministerial allowances, privileges of office, use of cars, working out arrangements for his own advantage, it was evident that he always looked after his own financial interest. He was reputed to have become rich, although he never did anything to disclose it. In any cabinet discussion about such matters, it was always clearly predictable that McEwen would look after himself first."

In the same cabinet was Sir William McMahon, a rich man who could never see anything wrong with drawing the age pension when in office. It was, after all, a right. Then at least.

By contrast, an earlier colleague, Sir Robert Menzies hardly ever claimed entitlements, even when travelling abroad. His daughter, Heather, has written of a man stingy with public money, and generous with his own. "When he travelled overseas he was given an allowance," she says. "If he gave an official dinner party, but included personal friends, he would pay for the whole thing itself. The result was that his allowance was never fully spent. So, after he came home, he handed back to Treasury whatever was left."

My advice to the modern politician is not to try this at home. Such behaviour could only draw unwelcome attention to colleagues of a different stripe.