Responding to Michael Ashcroft's non-dom admission earlier this week - which came just minutes before a Cabinet Office disclosure on the subject - Peter Mandelson accused the billionaire Belizean of trying to "steal the election" yesterday, and called on the Conservative Party to repay all money donated by him.
Mr. Mandelson also renewed his demand for an inquiry by the Lords Appointments Commission into the "solemn and binding" undertaking made by the Conservative Party deputy chairman in 2000 to become a "permanent resident" of the UK as a pre-condition to receiving a seat in the House of Lords.
Mr. Ashcroft claims shortly after his peerage was announced the civil service agreed that he need only become a "long-term resident" of the UK to sit in the Lords. That deal allowed him to remain non-domiciled for tax purposes and avoid paying an estimated £127m in UK taxes.
"However, this cannot be the condition he was required to meet in 2000," Mr. Mandelson said, "because the 'long-term resident' rule was only introduced in April 2008 - eight years after he made his promise."
The Lords Appointments Commission refuses to countenance a "retrospective investigation", however, since it did not exist when Mr. Ashcroft was ennobled - at that time the (now-defunct) Political Honours Scrutiny Committee held sway.
But Mr. Mandelson said: "It is not acceptable for the authority simply to say, 'We are an independent commission now. We didn't exist then. We don't have the papers.' Those papers exist. Somewhere, someone along the line made a deal with Lord Ashcroft the terms of which he has chosen to dodge for 10 years."
Mr. Mandelson also called on the Electoral Commission to hurry up and publish the results of its inquiry into donations made to the Tories by Mr. Ashcroft's company Bearwood Corporate Services. Mr. Ashcroft has been "spending [money] in countless marginal seats across the country trying to buy seats in order to steal the election," Mr. Mandelson said.
"The public is entitled to know. This is a matter of democracy, how we function, the rights we have, and what we need to know about how someone like Ashcroft has operated in the dark for so long, manipulating our electoral system in order to gain advantage for one party."
In addition to calls for the Electoral Commission to publish its report and the Lords Appointments Commission to commence an inquiry, Liberal Democrat Chris Huhne has called on HM Revenue & Customs to launch an investigation.
Meanwhile, David Cameron and William Hague still refuse to say when they learned Mr. Ashcroft was a non-dom. When pressed for details, Mr. Cameron replied: "I admire people who try to flog a dead horse. But the horse is dead and should no longer be flogged."