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LONDON - A senior detective will face a committee of MPs to explain his investigation into alleged political corruption that overshadowed former Prime Minister Tony Blair's last months in office.
John Yates, Assistant Commissioner of London's Metropolitan Police, has been summoned by the Public Administration Select Committee to give details of the 16-month probe into the so-called "cash for honours" inquiry.
Yates' team launched their investigation in March 2006 after claims that political parties had nominated people for seats in the House of Lords in return for cash.
Blair was quizzed by officers as a witness three times, the first serving prime minister to face questions in a criminal investigation. Two of his former aides, a donor, and a top Labour Party fundraiser were arrested during the inquiry.
Some analysts believe that the ongoing saga contributed to pressure from the party for Blair to step down early.
However, prosecutors announced in July this year that no one would face any charges, leading some politicians to criticise the length of the probe and its cost, estimated at about one million pounds.
"There are plenty of questions that need to be answered," Paul Rowen, a Liberal Democrat MP on the committee, said in a statement on his website.
"I want to know whether Assistant Commissioner Yates and his team got all the co-operation they were entitled to during their investigation.
"Was there obstruction from Downing Street or Mr Blair, and why at the end of the day, when it was clear that Mr Blair had driven a coach and horses through the honours regulations, were they not able to do anything about it?"
Media reports say that Blair had threatened to resign as prime minister if detectives had questioned him under caution as a suspect.
Newspapers have suggested that Yates may comment on this speculation and also whether detectives had faced any political interference.
He is also likely to be asked why officers carried out a dawn raid on the house of Ruth Turner, director of government relations in Blair's office.
Cash for Honours inquiry
2006
March 8 - Healthcare entrepreneur Chai Patel protests to the vetting committee for appointments to the House of Lords after his nomination for a peerage is blocked. It emerges he lent Labour A3;1.5 million ($4.15 million).
March 16 - Labour Treasurer Jack Dromey says he has been "kept in the dark" over undeclared loans. Tony Blair promises to change party funding rules in a bid to quell the growing row.
March 17 - Labour says it has received A3;14 million in previously undeclared loans from individuals.
March 21 - Police say they are investigating the Labour Party to find out whether it offered peerages to businessmen in exchange for loans. They say they have received three complaints about Labour under section 1 of the Honours Act 1925, which makes it illegal to sell state honours.
April 13 - Des Smith, a former adviser on Blair's flagship schools programme, is arrested in connection with the inquiry. He is released on bail pending further inquiries.
July 12 - Lord Michael Levy is arrested. Levy, Blair's personal Middle East envoy and chief fundraiser, denies any wrongdoing.
Sept 21 - Christopher Evans, founder of biotechnology company Merlin Biosciences, is the third person arrested. All three are released on bail without charge and deny wrongdoing.
Oct 23 - Police question Michael Howard, former leader of the opposition Conservatives, about the scandal.
Nov 16 - Police say they hope to send evidence to prosecutors in January. They say they have interviewed 90 people and have obtained "significant and valuable" material.
Nov 22 - Health Secretary Patricia Hewitt becomes first serving member of the cabinet to be questioned, as a witness not a suspect. Police subsequently question most other members of Blair's 2005 cabinet as witnesses.
Dec 14 - Blair is interviewed as a witness, becoming the first serving British prime minister to be interviewed by police in a criminal investigation.
2007
Jan 19 - Ruth Turner, director of government relations in Blair's office, is arrested on suspicion of perverting the course of justice and released without charge.
Jan 26 - Blair is interviewed a second time.
Jan 30 - Lord Levy is arrested for a second time, this time on suspicion of conspiracy to pervert the course of justice and is released without charge.
Feb 6 - Prosecutors say there is not enough evidence to charge Des Smith.
April 20 - Police send 216 page file to Crown Prosecution Service (CPS) after interviewing 136 people either as witnesses or suspects. CPS has to decide whether charges should be brought.
June 27 - Blair steps down as prime minister, handing over power to Chancellor Gordon Brown.
June 28 - Blair is questioned for a third time by London detectives investigating allegations of illegal political party funding. Officials will not confirm it.
July 20 - Prosecutors say they will not file any charges.
- REUTERS