Greece is in a tax evasion crisis. Using a variety of sources I estimated earlier this year that 27.5% of its economy was unrecorded giving rise to a total loss to tax evasion that could be as high as €19.2bn a year. Now you can argue with the figures, but few disagree that Greece is in the premier league of European tax evasion, outdoing Italy (just) and leaving Spain trailing in its wake, even if challenged for top spot by some of the more recent EU member states. In that case you would expect the Greek tax authorities to use any and every measure they can to collect their missing billions and in the process mitigate the impact of the most extreme austerity regime ever imposed on a modern democracy.

Well, you might expect that, but that's not what is happening. It's been an open secret for some time that the Greek tax authorities have had access to data on the identity of Greek residents holding bank accounts in Switzerland. It has also been widely known that they have shown a lack of willingness to use this information to tackle those listed. Unsurprisingly, given the severity of the measures being imposed on Greek people, this created resentment that reached the point where Kostas Vaxevanis, a Greek journalist, decided to publish the list of 2,000 names to which he believes the Greek tax authorities have access, but about which he alleges no action is being taken. His reward is to be arrested. His alleged crime is that he has illegally published the names of people without any evidence that they have evaded tax.

The paradox inherent in this action is extraordinary. While the existence of a Swiss bank account in your name is not evidence of any crime, it's no secret that Swiss banks have been used since at least 1934 by tax evaders from outside that country. That is not an accident, or chance: the Swiss introduced their draconian banking secrecy laws to prevent France making inquiries about high-ranking public officials, company directors and even clerics accused of evading tax by using its banks. History has a habit of repeating itself. The fact that a significant proportion of all funds held in Switzerland are illicit is now also widely accepted. The Swiss Bankers Association has agreed that proportion may be as high as 50%. The UK-Switzerland tax deal confirmed this year is built on the assumption that this is the case.

If Swiss bankers now acknowledge that this is the case let's not presume that those using these accounts did not know of the possibility. The Swiss banks made available an opportunity for organised crime to take place, and did so very deliberately. Tax evasion is crime: it is theft just like any other theft. Tax evasion in a Swiss bank account also never occurs by chance: it is a pre-meditated act. Worse, it is by definition the act of a person who does not need to use crime to make ends meet, unlike the supposedly much more villainous, by popular repute, benefit cheat, who in very many cases is simply trying to put food on the table. There is, in other words, no moral defence for this crime.

And yet, extraordinarily, the world is in denial about it. The biggest single leak of names from a bank came from HSBC in Switzerland, whose former chairman is Lord Stephen Green, now a Tory trade minister.

That list from HSBC, and other lists like it, are in the possession of HM Revenue & Customs in the UK. So far no one has come to court as a result. The impression given by the UK tax authorities is the same as the impression given in Greece, which is that these matters should be dealt with rather quietly and subtly, while the bankers and maybe lawyers and accountants, who no doubt played a hand in creating many of these arrangements, appear to be carrying on without hint of remorse or risk of prosecution.

The arrest of Vaxevanis in Greece rightly challenges this cosy position. A man who wants justice to be done has been arrested. In the meantime it is all too obvious justice is not being done, and lame excuses are being offered. It is said that we cannot pay for such lists, or that they were stolen in the first case. But there is a long tradition in many legal systems, including the UK's, of paying for information to secure prosecutions, and of turning a blind eye to the acts of those supplying it. You can be sure that a list of benefit cheats, however secured, would not be treated in the way this list has been.

And it is said, perhaps quietly but none the less definitely, that prosecutions in these cases do not pay: co-operation does. But that's just the "old boys" network at work. It's the typical attitude that the poor are motivated by the fear of prosecution while the rich get a quiet slap on the wrist, a modest fine and an instruction not to do it again while keeping much of the proceeds of their activity (which the UK approach on Swiss tax evasion guarantees now).

The UK, Greece and Europe are in crisis because of a lack of tax revenues, not because of overspending. All countries suffer significant tax evasion (and my research shows that the UK figure is much higher than admitted to by HMRC). The time has come to make explicit that tax evasion cannot pay, whoever does it. Time inside is the best way to deter this crime, most especially for those with reputations to lose. Prosecutions are needed now if reliable information is available, however sourced, both here and in Greece. And the last thing we need is for those who demand justice for corrupt bankers and their customers to be arrested. The time for a change of attitude towards the crimes of the rich has come: this may be the moment when Europe as a whole realises.