An investigation is to be launched into aspects of the inquiry into the death of Stuart Lubbock, whose body was found at the home of Michael Barrymore.
Stuart Lubbock was found dead at Mr Barrymore's Essex home
The Independent Police Complaints Commission said it had decided to investigate after receiving complaints from Mr Lubbock's family.
The complaints surround information Essex Police gave to a coroner and pathologist after Mr Lubbock's death.
Mr Lubbock, 31, was found dead at the entertainer's Essex home in March 2001.
Tony Bennett, the Lubbock family lawyer, said Mr Lubbock's family had made serious allegations about police officers.
In a letter to Mr Bennett IPCC commissioner Mehmuda Mian Pritchard said: "The investigation into the complaint will be carried out by a police force under our full direction and control."
The letter added: "I believe it is important for the investigation to be carried out by an external force."
Mr Bennett said Mr Lubbock's father Terry 62, who has campaigned for a new inquiry into his son's death, was delighted at the IPCC decision.
"Our complaint centres on information police gave to a coroner and a number of pathologists," said Mr Bennett.
"They said Stuart had been seen swimming in the pool earlier in the evening.
"We believe that this was not true and feel that the police should at least have made it clear that there was some doubt about it.
"Terry Lubbock has complained that there was either serious incompetence or some form of corruption.
"We are delighted that the IPCC is to investigate and we will help in any way we can. All Mr Lubbock has ever wanted is the truth about what happened to his son."
Essex Police conducted a lengthy investigation into Mr Lubbock's death but no-one was charged with any offences.
They announced in December 2006 they were reinvestigating the events at the house and the case remains open.
Mr Lubbock had been among a number of people at a party at Mr Barrymore's home in the hours before his body was found.
Post-mortem examination tests showed that he had suffered severe internal injuries which suggested sexual assault.
Alcohol, ecstasy and cocaine were found in his bloodstream.
A coroner recorded an open verdict following an inquest in September 2002.
A spokeswoman for Essex Police said officers were aware of the IPCC decision and would co-operate fully.
She said the force did not wish to discuss the allegations made by the Lubbock family while the investigation was pending.