Six years after the Independent Police Complaints Commission (IPCC) was founded, there are still concerns about the effectiveness and independence of policing the police, as BBC File On 4's Gerry Northam explains.
Nick Hardwick says deaths in custody have been reduced
The IPCC was set up to provide impartial investigations of complaints against the police in England and Wales but former Commissioner John Crawley, who left in 2008, says he is disillusioned with what it has achieved.
"Why should the public have confidence in a complaints system when they know that the odds are hugely stacked against having their complaint upheld and are even more stacked against them in terms of the prospect of a police officer who has done something wrong being held to account?" he told File on 4.
"The fundamental charge against the IPCC appeals system, for the past six years, is that it has not produced any significant change that anyone can point to in the fairness and rigour of the police complaints system," said Mr Crawley, who decided against applying for a fresh term on the commission in 2008.
The IPCC replaced the Police Complaints Authority (PCA) in 2004 following the 2002 Police Reform Act giving a public body powers for the first time to investigate the police directly. The PCA had merely overseen a self-investigation system.
Both the 1993 Macpherson Inquiry into the racist murder of Stephen Lawrence and Lord Scarman's inquiry into the Brixton riots had recommended the establishment of an independent body to investigate police complaints.
But according to Mr Crawley: "Very little of what was hoped for back in 2004, when the organisation was launched, has been achieved."
It is a fact that the commission only directly investigated a tiny proportion of complaints against police last year - just 88 of more than 31,000.
The Independent Police Complaints Commission
Hears appeals against the way a police force dealt with a complaint
Deals with mandatory referrals such as deaths in police custody
Can investigate a complaint directly
Can either manage a police force's investigation of a complaint or supervise an investigation
The remainder were investigated by the police force against whom the original complaint was made, in a minority of cases this was under the management or supervision of the IPCC.
Last year there were a further 4,600 appeals to the IPPC about the original forces' conclusions - 29% of appeals were upheld.
The IPCC's chair Nick Hardwick however believes the IPCC has ushered in substantial advances.
"I would say we've cut the numbers of deaths in police custody by half," he told the BBC.
Mr Hardwick added: "I would say more complaints in actual numbers are being substantiated than before."
Some lawyers, however, doubt the effectiveness of the IPCC.
Marian Ellingworth cites the case of her client Courtney Bland, a juvenile who was cleared of assaulting a police officer. She doubts the effectiveness of the IPCC.
The boy's family complained of wrongful arrest, assault and that the officer had used abusive language during a scuffle with Courtney when he was aged 15.
The IPCC rejected the family's appeal against the Metropolitan Police, although the force later made an out-of-court settlement of £25,000 with the family and offered an official apology.
"I think it shows that the prospect of civil litigation is a more effective way of getting a police force to sit up and put its house in order," said Ms Ellingworth.
But in Nick Hardwick's view the doubling of complaints the IPCC has to deal with about the police demonstrates public confidence in the commission.
"I can point to any number of cases where we have taken action against senior officers," he said.
And he added: "I'm not saying we don't need to improve, of course I'm not saying we don't get it right on every occasion, but I think the IPCC and the people who work for it do a difficult job and have a record they can be proud of."
File on 4 is on BBC Radio 4 on Tuesday, 19 January , at 2000 GMT, repeated Sunday, 24 January, at 1700 GMT. You can also listen via the BBC
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