Senior police officers avoid shooting investigation
Four senior police officers will not face misconduct hearings over claims they failed to declare evidence in relation to a suspected drug dealer's shooting.
Five men convicted in 2008 for the Staffordshire murder of Kevin Nunes were cleared on appeal in 2012.
But the IPCC said "no evidence of a cover up or of wilful omission" by any of the officers was found.
Police leaders said they were pleased with the outcome.
The body of Mr Nunes was found in September 2002 in a country lane in Pattingham, Staffordshire.
He had been shot in what was believed to be a gangland killing over drugs.
Levi Walker, from Birmingham, Adam Joof, from Willenhall in the West Midlands, Antonio Christie, from Great Bridge in the West Midlands and Michael Osbourne and Owen Crooks, both from Wolverhampton, were found guilty of murder after a trial at Leicester Crown Court in 2008.
They were given minimum tariffs of between 25 and 28 years.
However, the Court of Appeal overturned the convictions in 2012, with Lord Justice Hooper criticising a "very bad case of non-disclosure" regarding the credibility of a witness, leading to "what appears to us to be a serious perversion of the course of justice".
An investigation was launched into the conduct of current Staffordshire Chief Constable Jane Sawyers, Gloucestershire Chief Constable Suzette Davenport, West Midlands Assistant Chief Constable Marcus Beale and Adrian Lee, who retired as chief constable of Northamptonshire Police last year.
All four were officers at Staffordshire at the time of the murder investigation.
The Independent Police Complaints Committee (IPCC) said it looked at "disclosure issues" before the 2008 murder trial and "how a protected witness was dealt with by Staffordshire Police" but "no evidence of a cover up or of wilful omission by any of the four senior officers" was found.
IPCC deputy chair Sarah Green said: "This has been an extremely complex and lengthy investigation.
"There is broad agreement there were serious failings at Staffordshire Police following the murder of Kevin Nunes in 2002 and the conviction of five defendants for that murder in 2008.
"However, cases for gross misconduct or misconduct have been rejected by the appropriate authorities who are responsible for holding misconduct hearings.
"After careful consideration I have accepted the appropriate authorities' assessments and decided not to issue directions that misconduct hearings be held."
Mrs Sawyers said it was right her actions were "thoroughly investigated".
But she said the management of the investigation by the IPCC "resulted in a lengthy, costly and disproportionate investigation from which there are no winners".
In a statement released by Gloucestershire's Police and Crime Commissioner Martin Surl, Ms Davenport said she had always tried to carry out duties "diligently and professionally" and was "pleased and relieved" the IPCC matters were concluded.
Northamptonshire PCC Adam Simmonds said even though Mr Lee retired last year, this had been "a real burden upon him and his family". Mr Simmonds said he was "very pleased" all those concerned could "move on with their lives".
West Midlands Police declined to comment.
Two detective constables were found to have a case to answer for misconduct in respect of one matter, the IPCC said.
The watchdog said one detective constable was given management advice, while the other retired on health grounds.