Howard questioned in cash-for-honours inquiry

Michael Howard, the former Conservative Party leader, has been questioned by police in the "cash for peerages" investigation, possibly clearing the way to a future police interview with the Prime Minister.

Mr Howard was asked about the wealthy car dealer Robert Edmiston, whom he put forward for a peerage in 2005. The year before, Mr Edmiston had lent the Tory party £250,000.

The nomination was eventually blocked by the Lords Appointments Commission, as were those of Labour supporters put forward by Tony Blair including Sir Gulam Noon, Dr Chai Patel, Barry Townsley and Sir David Garrard.

But Mr Howard made clear he was questioned as a witness rather than a suspect. The "short" interview was at his home, the Tory party said. Scotland Yard has already interviewed six Conservative supporters. They have also spoken to Lord Laidlaw, a tax exile in Monaco, Johan Eliasch, the sports tycoon who lent £2.6m, and Lord Ashcroft, the former party treasurer who lent £3.5m. A party source said police had told the party they wanted to interview between 30 and 40 Tories and said several had refused.

The Independent has learnt that deputy assistant police commissioner John Yates, the detective leading the investigation, has been ordered by a Commons select committee to give it an update on his inquiry. MPs on the Public Administration Committee have delayed their own inquiry pending the police investigation after an appeal by Mr Yates to avoid compromising a possible prosecution under a 1925 Act, which makes it an offence to sell honours, or under the 2000 Act regulating the funding of political parties.

Several high-profile figures in the Labour Party have been arrested. Lord Levy, the high-value Labour fundraiser, was held briefly in July as the investigation crept closer to Mr Blair. Police also interviewed under caution the property developer, Sir David Garrard, Sir Gulum Noon, known as the "curry king"and the city broker Barry Townsley, at their solicitors' offices.

Senior Conservative figures had expected Mr Howard to be interviewed. The Tory party said in July when the police net was spread to include the Conservatives that the difference between Robert Edmiston's loan and Labour's loans was that his was declared to the Lords Appointments Commission.

Police are not expected to interview Mr Howard's predecessor, Iain Duncan Smith, or David Cameron, and are understood to be close to finishing their work on Mr Edmiston's nomination.

The investigation so far

Police have questioned about 50 people, including more than a dozen under caution. Three have been arrested and bailed. They are Lord Levy, the Labour fundraiser and friend of Tony Blair; Sir Christopher Evans, a biotechnology entrepreneur, and Des Smith, a headteacher who helped wealthy backers for specialist schools. Ruth Turner, the Prime Minister's director of government relations, was questioned this month. Ian McCartney, the former Labour chairman, and Lord Sainsbury, the Science minister, are among those understood to have been interviewed, but not under caution or arrest.