When George Osborne attacked tax avoiders as morally repugnant last March, he must have thought this would bring him easy political gains.

It has not worked out quite like that. Rather a lot of Tory donors and sympathisers have turned out to be tax avoiders.

And some major companies seem to be able to persuade Revenue officials to interpret their tax liabilities quite generously.

Meanwhile, it is painfully obvious that Her Majesty’s Revenue & Customs are simply not very good at combating the increasingly ingenious schemes of tax avoidance experts.

This is especially annoying to normal taxpayers, who never dream of tax avoidance, yet find HMRC hot on their trail, suspicious and demanding, even when they try to submit accurate and timely tax returns.

The sneering remark of the American hotel magnate Leona Helmsley that ‘only little people pay taxes’ seems to be coming true here as well.

Now, thanks to Channel 4’s Dispatches programme, we learn that members of HMRC’s board have links to companies which themselves face suggestions that they engage - quite legally - in tax avoidance

To cut costs, Revenue & Customs signed a deal with an offshore firm that has now avoided paying millions of pounds in tax

Senior revenue and customs officials appeared before the public accounts committee today to be told that their department scored a "massive own goal" by using an offshore company to manage its properties.

In 2001 the Inland Revenue and Customs and Excise, later merged to form HMRC, signed a 20-year contract with Mapeley STEPS Contractor Ltd, handing over ownership and management of 60% of HMRC properties to the private contractor.

Lesley Strathie, chief executive of HMRC, told the public accounts committee she is not embarrassed by the deal, despite the fact that Mapeley avoids paying UK tax by holding its assets in Bermuda.

Nightclubs in Scotland, hair salons in Northern Ireland and car salesmen in Yorkshire are among the latest targets of tax investigators as HMRC continues its crackdown on small business tax dodgers.

HM Revenue & Customs has identified the professions as high-risk and will send specialist teams to visit traders to examine their records and carry out other investigations.