The IPCC should have a statutory power to force implementation of its findings and in the most serious cases it should instigate a "year on review" to ensure that its recommendations have been properly carried out, the committee said.
Failure to do so would result in an investigation by Her Majesty's Inspectorate of Constabulary and the Police and Crime Commissioner.
The report said the IPCC lacks the resources necessary to "get to the truth" - it has a smaller budget than the Professional Standards Department of the Met Police.
IPCC investigators should be able to take immediate control of a potential crime scene during the crucial "golden hours" and early days of an investigation into deaths and serious injury involving police officers, the committee recommended.
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