A thriving tax avoidance sector is a sign of a society that has got one thing right.

Playwright Tom Stoppard once wrote of the tabloid press: 'Junk journalism is the evidence of a society that has got at least one thing right, that there should be nobody with the power to dictate where responsible journalism begins.’

Something similar needs to be coined in defence of the equally unfashionable practice of designing legal side-steps to tax obligations. How about: 'A thriving tax avoidance sector is the evidence of a society that has got at least one thing right: that the rule of law stands above arbitrary power.'

Don't expect it to catch on. Social media megaphones which (rightly) sound off about the importance of due process when it comes to proceedings against an accused terrorist fall silent when governments bend laws to nail tax avoidance. Politically, there are few easier targets than lawyers who test the boundaries of tax liability. 

The reason for bringing this up now is of course HM Revenue & Customs' widely trailed publication yesterday of proposals to turn into effect the 2016 budget's pledge to crack down on 'enablers of tax avoidance'. In particular, the ideas for ensuring that professional advisers should suffer dire consequences if a scheme on which they provide advice is later shot down in court. 

Experts quick to point out the dangers. Fiona Fernie, partner at international firm Pinsent Masons, suggested that some of HMRC's proposals could end up capturing traditionally accepted tax planning.

'The wording of the proposals suggests that measures will cover not only all schemes counter-acted by the general anti-abuse rule or notifiable under disclosure of tax-avoidance schemes but also those which have simply been the subject of a targeted avoidance-related rule or "unallowable purpose test" contained within a specific piece of legislation. This is incredibly wide-ranging.'

Fernie also raises the issue — unthinkable in other contexts — of retrospectivity: will purveyors of professional advice, given in good faith and with reasonable care to accord with the law, be hammered for sins in the past?

The assumption, of course, is that HMRC is floating extreme ideas on the basis that it will be knocked back halfway. Tax lawyers inured to such dealings will no doubt grin and bear it. Almost by definition, they are pragmatists (notwithstanding the odd human rights challenge). 

Perhaps it's too late; perhaps the line of arbitrary power has already been crossed with the general anti-abuse rule, but is there not a broader principle at stake here? That a lawyer should be allowed to advise a client on the black-letter status of a strategy without fearing comeback from the state if the strategy is later ruled out of bounds?

Is the existence of such a practice sector not evidence of a society that has got at least one thing right? 

Michael Cross is news editor at the Gazette