The Sun is offering a £50,000 reward "to catch the killer of Joanna Yeates", the landscape architect whose body was found in Bristol on Christmas day.

The newspaper's managing editor, Graham Dudman, told Sky News that its move was inspired by readers.

"This is one of these rare, and unfortunate cases, that has really touched the nation and we have had a huge response from our readers imploring us to help," he said.

According to the paper, the "baffled" Avon and Somerset police force support the reward offer. It quotes the man leading the murder inquiry, Detective Chief Inspector Phil Jones, as saying:

"I am grateful for the generosity of The Sun newspaper, and I am sure that Jo's family will be touched by this kind gesture."

Maybe they will. There is a long history of popular newspapers offering rewards in such circumstances, though there's precious little evidence of them having any positive effect.

The offers are really made in order to sell more newspapers. And, in the specific case of the Sun on this occasion, it is surely designed to deflect criticism over its scurrilous coverage of this murder thus far.

Its reporting of the case following the police arrest of Yeates's landlord, Chris Jefferies, has been anything but admirable. It described the man in a headline as "weird, posh, lewd and creepy" over heavily slanted copy.

The Sun was not alone, of course. The Daily Mirror carried a vile and absurd piece, Paedophile colleague of Joanna Yeates murder suspect Chris Jefferies abused boy at the flat where Jo lived. Even if true, its intent - to cast doubts on Jefferies' character by linking him to a totally unrelated sexual crime - was obvious.

Several papers - and news agencies, and broadcasters - ran material that was laced with innuendo simply by the way it presented otherwise innocent "facts" and quotes.

I agree with the Daily Telegraph blog posting by Guy Walters, You can make anyone look guilty of murder.

Example from the Daily Star, quoting a former pupil at Clifton College, where Jefferies had been a teacher: "It's all in his eyes and hair. People were scared of him."

I also agree with the view of blogger Anorak that Jefferies has been "monstered by the media until he morphed into something that resembled a blue-haired, child worrying, potential serial killer."

The insinuations of guilt continued after Jefferies was released on police bail. The Daily Star reported that he was "in hiding" having been "advised to stay away from his home." Why? Because of prejudice created by media coverage, of course.

Clearly, the media no longer take seriously the contempt of court act. Peter Wilby, writing in the New Statesman, argued that in recent years "the police, the government, the courts and the Press Complaints Commission have allowed and even colluded in what amounts to a complete rewriting of legal convention."

There is another aspect to this case that deserves proper media scrutiny, as Bristol blogger Martin Booth suggests on his Bristol Culture site. That's the behaviour of the Avon and Somerset police force.

Its prior suspicion of journalists, and occasional hostility towards them, did not prepare its officers for dealing with a media feeding frenzy.

According to Booth: "The police have carefully drip-fed news about this case and obviously want to control the media reporting as best they can."

News management is foolish. In the aftermath of this tragedy, everyone involved – media editors, senior police officers, the attorney general - should study what has happened.

None of them have covered themselves in glory.

Sources: The Sun/Sky News/Anorak/Bristol Culture/New Statesman