In 2011, a trial of four men charged with Daniel Morgan's murder in 2008 collapsed following alleged failures by the police and the Crown Prosecution Service.
At the time, Det Ch Supt Hamish Campbell of the Metropolitan Police Service said:
Despite six criminal investigations, it has been claimed that police corruption prevented private investigator Daniel Morgan's murder in 1987 from being solved.
Mr Morgan's brother Alastair told the BBC's Newsnight: "If we're going to deal with corruption in the police force, we have to look at it straight in the eye.
"We have to see how it works, the nuts and bolts of it, where it started, what decisions were made."
It is widely expected that Home Secretary Theresa May will make an announcement on an independent judge-led inquiry into the murder of Daniel Morgan.
The private investigator was found with an axe in his head in a London pub car park in 1987.
It has been claimed that police corruption prevented the murder from being solved despite six criminal investigations.
A former police officer has told the Leveson inquiry that she believes people at the News of the World were involved in an attempt to 'derail' a murder investigation.
Jacqui Hames said she believes 'there was some collusion between people at the News of the World and people suspected of committing the murder of Daniel Morgan.'
Her husband Chief Superintendent Dave Cook was a high profile detective on the investigation, he was put under surveillance by the newspaper she says.
When an explanation was sought from the News of the World, she says the then News International boss Rebekah Brooks told Scotland Yard that they had been investigating suspicions that Jacqui Hames was having an affair with her husband, and that the newspaper hadn't realised they were married.
This explanation was described by Jacqui Hames today as 'absolutely pathetic'.