Just how pleased should we be that George Osborne has persuaded his Swiss counterparts that they should pay some compensation for the fact that billions of pounds of British tax dodgers' money is currently parked in secret bank accounts in their country?

Well, about as pleased as we would be if someone had robbed a British bank, fled to Switzerland and then got away with it, scot-free, apart from the inconvenience of the local authorities casually handing back some of the proceeds.

It is fairly easy to understand the pragmatism of this deal, which will see Switzerland pay the UK around £380m upfront, in lieu of unpaid tax, by British account holders in the country, with the promise of more to come.

It is, however, a thoroughly unhappy compromise. For one thing, it is deeply unfair on law-abiding British taxpayers who hand over every penny of tax they owe and would not dream of trying to hide their wealth.

That we are giving up on trying to identify those who break the law simply because we're getting something back from them via the Swiss - but certainly not everything they owe - is a betrayal of the honest taxpayers and an increased incentive for more people to evade paying tax by following their lead.

And for another thing, the deal is unfair on Britain's banks (an industry the Treasury is usually quick to defend).

We have now accepted that Switzerland's financial sector has an unfair advantage over our deposit takers because British customers are getting away with paying less tax there on their money than here. It's a reward for colluding with criminality.

Then there are the people who have already had the courtesy to come forward under HM Revenue & Customs' previous offers of lenient treatment.

It turns out that the treatment would have been even more lenient if only they had not been so honest.

Finally, we should worry about the precedent we are setting with this deal. Christian Aid, for one, thinks the arrangement will make it far tougher for less wealthy and politically influential nations to chase their own tax-evading citizens - and thus the recoup the revenues they need even more desperately than we need ours.

Switzerland does not have an automatic right to banking secrecy that it is entitled to protect at all costs.

This behaviour is not acceptable from a country that claims to be a good international citizen. Nor do other countries accept that the UK's pragmatism is the only way to get results.

The US authorities, for example, have chosen to take on Switzerland's banks one by one and they have won much greater levels of disclosure from them.

We should do the same, rather than letting tax evaders get away with it.