A Sikh detective sergeant is suing the Daily Mail for libel over allegations he orchestrated a race hate campaign, the BBC News website has learned.
Det Sgt Virdi was previously cleared of any wrongdoing
Gurpal Virdi was sacked in 2000 after he was falsely accused of sending racist mail to black and Asian staff at Hanwell police station in west London.
Mr Virdi won £150,000 in damages and an apology from the Metropolitan Police after he was cleared of any wrongdoing.
"The Daily Mail's allegations are completely untrue," said Mr Virdi.
The newspaper was contacted by the BBC for a response to the libel action over the article dated 22 April 2006, but it is yet to reply.
A Metropolitan Police Authority report on the handling of Mr Virdi's case criticised the force's disciplinary procedures.
Mr Virdi, who returned to work for the Met Police in 2002, has vowed to find out who was behind the race hate campaign.
His solicitor Jeremy Clarke-Williams said his client denied "absolutely and categorically" the Daily Mail's allegations.
"These allegations are serious and damaging," he said.
"Mr Virdi has been through any number of hoops and hurdles to demonstrate his innocence."
He said the newspaper was due to serve a defence to the claim on 18 April.