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:
We recognise the severe disappointment this will cause and how deeply upsetting it is to Daniel's family and friends.
Thousands of lines of inquiry have been pursued since 1987 and over three quarters of a million documents have accrued and been examined.
On behalf of the Metropolitan Police Service I sincerely apologise to Daniel Morgan's family and it is with considerable regret that a trial cannot proceed.
This current investigation has identified, ever more clearly, how the initial inquiry failed the family and wider public. It is quite apparent that police corruption was a debilitating factor in that investigation. This was wholly unacceptable.