A Labour MP has backed demands for a public inquiry into the deaths of three men during the summer riots in 2011.
Birmingham Ladywood MP Shabana Mahmood described a report by the police watchdog into the deaths of Haroon Jahan, Shazad Ali and Abdul Musavir as a "failure" which had brought the victims' families no closer to justice.
The report, published by the Independent Police Complaints Commission (IPCC), found a senior officer had been reckless in offering immunity to witnesses to the deaths in Winson Green, Birmingham.
Eight men were acquitted in July 2012 of murdering the three victims after jurors at Birmingham Crown Court were told another senior officer had lied about the disclosure of evidence in the case.
In a letter to Home Secretary Theresa May, Ms Mahmood claimed the IPCC report "served no-one" due to its restricted terms of reference.
The MP wrote: "Yesterday the Independent Police Complaints Commission published its report into the West Midlands Police investigation.
"It ruled that one officer alone had acted recklessly. This officer has since retired. A second officer, who had been previously accused by a judge of having lied on oath, was found to have no case to answer.
"Eight men were prosecuted, but none convicted in a trial which almost collapsed because of issues with the police investigation.
"It is clear to me that this report is a failure."
Ms Mahmood's views echo those of Tariq Jahan, whose son, Haroon, was trying to protect shops from looters when he was hit by a car near a petrol station on August 10, 2011.
Mr Jahan has called for a public inquiry into the actions of West Midlands Police and the Crown Prosecution Service during the murder inquiry.
In her letter to the Home Secretary, Ms Mahmood added: "I am convinced that a full public inquiry is needed to get to the truth of the matter and I would like to ask you formally to instigate this and furthermore, to meet with Mr Jahan as a matter of priority."
Following the publication of the IPCC report, West Midlands Police said the severity of the allegations made during the trial had led the force to immediately refer the matter to the watchdog.
Assistant Chief Constable Gary Cann said: "The independent investigation shows no officer from West Midlands Police deliberately misled the trial at Birmingham Crown Court."
A Home Office spokesman said: "The IPCC's conclusions are deeply troubling - it is clear that the professional standards expected of all police officers were not met in this individual case.
"It is vital we do not allow the actions of a few officers to undermine public confidence in policing.
"We are aware Mr Jahan's MP has written to the Home Secretary. Any formal request for a public inquiry will be considered once it is received."