The SDLP and Sinn Fein analysis that the Police (Northern Ireland) Bill significantly dilutes the reform proposals was boosted yesterday with a member of the Patten commission, Prof Clifford Shearing, describing the Bill as "gutting" the Patten report.
Nationalist and unionist politicians have intensified pressure to force the British government to meet their diametrically opposing views on how police reform should be implemented.
And as the Bill begins its third reading in the House of Lords today, Ulster Unionists are to table an amendment at Mr David Trimble's behest, and supported by the Conservative Party, calling for a moratorium on police reform.
The intervention by Prof Shearing, director of the Centre of Criminology at the University of Toronto, angered the Northern Secretary, Mr Mandelson, who said: "Everyone has to live in the real world, and that includes former members of the Patten commission."
"I fundamentally disagree with his analysis," he added, speaking in Lisburn yesterday.
The Canadian academic's article in yesterday's Guardian newspaper was trenchant: "The Patten report has not been cherry-picked - it has been gutted," he wrote.
"The core elements of the Patten commission's report have been undermined everywhere," added Prof Shearing. "The Bill before parliament dismantles the foundations on which the Patten commission's plan was built."
Prof Shearing's analysis generally supports the SDLP and Sinn Fein complaint that, aside from the emotive issues of the RUC name and symbols, the Bill attacks Patten's attempt to make the proposed new Police Service of Northern Ireland more accountable to Northern politicians and to the Northern public.
The professor claims that the Bill severely restricts the powers of the proposed Policing Board to hold the new police service and its chief constable accountable for their actions.
Meanwhile, three Ulster Unionist peers will today table an amendment in the House of Lords for a halt to police reform. The UUP leader and First Minister, Mr David Trimble, said: "Many of the Patten reforms were designed for policing in a peaceful environment."
But he said that following recent dissident republican paramilitary activity it was clear there was still a significant security threat and that the British government had "a duty to retain the present RUC operational structures and resource allocation levels".
British and Irish officials have been in intensive contact this week in an attempt to find a resolution to the policing question.
Mr Mandelson, caught between the conflicting stances of unionists and nationalists, said policing changes would proceed but added that he would take into account the continuing security threat when implementing reform.
"I believe the changes are right for policing in Northern Ireland and that's why I intend to carry on with them. Obviously we have to be conscious of the fact that violence has not gone away in Northern Ireland and we will proceed with these changes in a way that is sensitive to that," he said.
The DUP Assembly member, Mr Nigel Dodds, described the UUP amendment as "too little, too late". He added: "Mr Trimble is bluffing once again. He talks tough but it is clear he has no intention of taking action which would have the effect of making the British government pull back from the destruction of the RUC."
