By Mark White, Home Affairs Correspondent
More than half of Britons believe there is a culture of cover-ups within the police, a Sky News poll has found.
A total of 53% of members of the public questioned in the survey agreed that forces try to hide officers' wrongdoing. Just 18% of people polled disagreed that cover-ups take place.
The findings follow a series of controversies in which police have been accused of making serious mistakes and then attempting to shield officers from blame.
In 2012, it emerged that scores of statements from officers involved in the Hillsborough disaster in 1989 had been doctored to remove evidence of police failings.
Since September that year the Metropolitan Police has been embroiled in a damaging row with the former Chief Whip Andrew Mitchell, over whether he had called an officer guarding Downing Street a "pleb".
And last week the Met faced criticism in the wake of the shooting of Mark Duggan, whose death in 2011 prompted widespread rioting and looting.

An inquest jury found that armed police had acted lawfully in killing Mr Duggan, but his family have insisted officers shot an unarmed man.
However, the Sky News poll - commissioned as part of a series of reports on the police entitled A Fair Cop? - found that despite these incidents, a large majority of the public still trust officers.
Asked whether their trust in police had changed over the past five years, 62% of those questioned said it had stayed the same, while 31% said it had gone down.
A total of 72% said they would trust the police to act if they reported a crime and 67% would trust officers to deal with them if they were the victim of a crime.
In relation to the conduct of officers over Hillsborough, 44% of those questioned said they now trust the police less, although 49% said it had made no difference.
Most people said the Mark Duggan case had not hit their trust in police The so-called 'Plebgate' affair prompted 51% of those questioned to say they had less trust in police, with 43% saying it made no difference.
However, 61% said the Mark Duggan case had not affected their trust in police. A total of 21% said they had less faith in officers, a number that increased to 40% among people who described themselves as non-white. 15% said they now trusted the police more.
Regarding police tactics, 60% of people who took part in the poll said they believed that 'stop and search' - a policy that ethnic minorities claim unfairly targets them - does more good than harm.
However, the same number of people questioned said they did not believe police should be able to use people's ethnic background to decide who to stop, a strategy known as racial profiling.
:: The Sky News poll was conducted by Survation who questioned 1,005 people earlier this week.
:: Watch Sky News live on television, on Sky channel 501, Virgin Media channel 602, Freeview channel 82 and Freesat channel 202.
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