More than 30 US politicians, among them seven members of a defence procurement committee, are being investigated in congressional ethics inquiries into influence-peddling, according to a document leaked accidentally on to the internet.

The disclosure sheds light on a process by which billions of dollars a year are spent on defence projects that the Pentagon does not want and which limits funds available for US military operations in Iraq and Afghanistan.

House Representatives named in the document include John Murtha, the chairman of the House Defence Appropriations Sub-committee, who added so-called “earmarks” worth more than $100 million (£61 million) to last year’s defence budget and received $743,000 in campaign contributions from defence contractors. The contributions were funnelled through the PMA Group, a lobbying company set up by a former aide to Mr Murtha which closed after being raided by the FBI this year.

Five of the seven members named in the leaked document are Democrats, which is an embarrassment for Nancy Pelosi, Speaker of the House, who pledged to “drain the swamp” of corruption and excessive corporate influence on Capitol Hill.

This week President Obama signed a Defence Authorisation Bill providing $680 billion in military spending for the coming year, including $2.5 billion for ten transport aircraft even though the Pentagon said that it has enough of them. The Bill authorises funding for an alternative engine for the F35 joint strike fighter that the Air Force says it does not need and a destroyer that the Navy says is obsolete.

Mr Obama noted that the Bill scrapped a presidential helicopter and an unproven airborne laser but he admitted: “There’s still more waste we need to cut.” He pointed to $296 billion of cost over-runs.

The practice of earmarked military spending is based on the right of congressional representatives to award no-bid contracts to defence companies, usually in their own states, whether or not the Department of Defence approves them.

That entitlement has fostered a culture of mutual dependence between lobbyists and politicians that has proved impossible to eradicate.

No specific wrongdoing is alleged in the 22-page report of the Ethics Committee but it revealed an inquiry of House members suspected of “accepting contributions or other items of value in exchange for an official act”.

Six members received contributions of $6.2 million and sponsored earmarks worth $200 million for PMA clients, according to the Congressional Quarterly and Taxpayers for Common Sense, a watchdog.

The PMA was set up by Paul Magliochetti. James Moran, who is also on the subcommittee, told The Washington Post: “When you wanted to raise money for the Democratic campaign committee he was always the first one you went to.” The smell of Sleaze is the last thing that Mr Obama or Mrs Pelosi want lingering in the corridors of in Congress as they try to coax Republicans to back their health reforms. A series of corruption scandals destroyed what remained of the Republican majority’s credibility in the waning months of the Bush era, but conservatives pounced on the PMA affair yesterday. “Clearly the Democrats were not serious when they said they would clean up the House of Representatives,” one said.

Surplus to requirement

Up to 20 more F22 fighters could be built next year at $145 million apiece even though they were designed for dogfights against Russian MiGs and, as one expert noted, “the Taleban doesn’t have an air force”. The US will also build a $2.7 billion DDG1000 destroyer that its Navy does not want. In all, taxpayers will fund nearly 800 defence or defence-related projects that the Pentagon has not requested

The most egregious example of unwanted hardware that Congress will still fund is the C17 transport. The Pentagon says it has enough of its newest heavylift aircraft but Boeing has spread its manufacturing across 43 states and lobbyists claim that 30,000 jobs depend on it. A total of $2.5 billion has been earmarked to build up to ten more

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