Every tax return should be made public in an attempt to prevent people avoiding paying their fair share, a Labour peer has said.
Lord Dubs made his call as the Government came under pressure to reveal more details of the tax avoidance scheme used by comedian Jimmy Carr.
Mr Carr is reported to have used an aggressive - but legal - strategy to channel cash through Jersey-based company K2, allowing him to pay income tax at rates as low as 1%.
At question time in the House of Lords, Labour's Lord Clinton-Davis said "thousands of extremely rich people" were "engaged in tax avoidance schemes" and called for an all-party committee to look into the "atrocious situation".
And Lord Dubs asked Treasury minister Lord Sassoon: "Wouldn't it be helpful if all tax returns were in the public domain?"
Labour Treasury spokesman Lord Davies of Oldham said legislation passed in 2004 meant that accountants had to submit to Her Majesty's Revenue and Customs (HMRC) "any scheme that leads to tax avoidance".
He demanded: "Was this implemented in the famous case of Jimmy Carr? Did his accountant inform HMRC? If so, what was done about it and if they hadn't, when is the Government going to act?"
Lord Sassoon said Lord Dubs' suggestion was "too radical".
And he told Lord Davies: "Individual taxpayer confidentiality is something that is very important and the prime reason we are not going to see individual tax returns published and I am not going to comment on any particular case. That particular case has had a lot of airing in the last couple of weeks."
He told peers the Government was consulting on a "general anti-abuse rule" and attempting to ensure that more schemes, which lead to an estimated £5 billion of tax avoidance a year, were closed down.
Five biggest taxpayer stings
Peer pushes for tax returns to be public
Most recently HM Revenue & Customs let Vodafone off the hook - for quite a sum. Vodafone paid out just £1.25 billion despite an original tax bill being closer to £8 billion (HMRC has always refused to reveal how much it thought the Vodafone final bill was). The episode was made even more shaming and painful because Vodafone was given several years to come good with the cash owed - even though it was sitting on a substantial cash pile at the time.
The Exchequer is estimated to have lost around £10 million to Goldman Sachs recently through an 'error' made by HMRC. The episode relates to an employee benefit trust run by Goldman allowing employees to take non-repayable loans that had no National Insurance contributions tied to them. HMRC did claw back the full amount from more than 20 businesses - but not Goldman. HMRC remains cagey about the details of the deal. Little HMRC accountability or transparency.
Huge problems with QinetiQ, the former Defence Evaluation and Research Agency, or DERA. A lack of clarity on contractual arrangements at the outset didn't help, allowing private equity company Carlyle to hammer the price down (why would you start negotiations when you didn't know the company's true value?). The Ministry of Defence behaved, it was said, like "an innocent at a table of card-sharps". Estimated cost to the taxpayer - £90 million. Huge sums were later made by QinetiQ management when the company listed.
The TaxPayers' Alliances estimates £2.7bn worth of taxpayer cash was wasted with a super-expensive 'National Programme for IT in the NHS'. The Department of Health, in the end, had very little to show for it as a consequence. Another example of poor management and a seemingly ingrained inability to provide taxpayers' with value for money.
"BT is paid £9 million to implement systems at each NHS site, even though the same systems have been purchased for under £2 million by NHS organisations outside the Programme", the Commons Public Accounts Committee noted.
Contentious. The Office for National Statistics estimated this has declined 3.4% since 1997, "with inputs increasing by 38%." The Centre for Economics and Business Research estimate that this inefficiency costs the taxpayer £58.4 billion a year.
Given the above record, are there any deals that the taxpayer has actually won out on? Not many, but the one successful project was the roll out of new Jobcentre Plus offices. It came in £314 million under budget, claims the Taxpayers' Alliance. A small cheer.