Newspaper editors' plans to launch a reformed press watchdog without statutory underpinning is a "charade", the Hacked Off group campaigning for tougher regulation has said.

At a press conference organised by Hacked Off in Westminster on Thursday, Natalie Fenton, professor of media and communications at Goldsmiths University, said that unless a new body to verify the performance of the watchdog was validated in law "everything else is pointless".

She condemned David Cameron's attempts to push through a private deal with newspapers and said victims' voices were not being heard.

Baroness Hollins, a cross-bench peer, whose daughter Abigail Witchalls became of interest to the press when she was paralysed after being stabbed in the neck in 2005, called for Cameron to implement a press law recommended by Lord Justice Leveson in his report last week.

She said her family had endured press harassment on and off for five years and although the reporting of her daughter was "sympathetic" the majority was not "accurate or ethical", including a revelation by the News of the World that she was pregnant when she was stabbed .

"I just don't think there is a place for the sensationalism to which my family and daughter were subjected," Hollins added. "I would support something in law to verify that the future press regulator is actually fit for purpose. I do not believe that this can be left entirely to the owners of newspapers."

Editors of all national newspapers have agreed to implement 40 of the 47 recommendations made by Leveson.

The proposed new regulatory body will have serving editors on its board, like the discredited Press Complaints Commission, and will have the powers to levy fines of up to £1m.

Fenton said: "It is simply a charade for the politicians and the editors to get together and pick out some of the recommendations and say these are acceptable or not and take out the heart and soul of the Leveson recommendations, which provide the backbone for establishing a fair system going forward.

"We find ourselves very quickly in a smoke and mirrors situation."

She added that editors were trying to remove the "heart and soul" of the Leveson report's recommendations by ignoring the ones that did not suit them.

It emerged on Wednesday that Salman Rushie is among more than 143,000 signatories of the Hacked Off petition calling for statutory underpinning for the new press regulator.

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