The Northern Secretary, Mr Peter Mandelson, will find himself caught in Conservative, Unionist, SDLP and Labour crossfire in the Commons this afternoon, when MPs begin the Second Reading debate on the controversial Police (Northern Ireland) Bill.
Mr Seamus Mallon, Northern Ireland's Deputy First Minister, will voice mounting nationalist anger at the failure of the Bill to carry through key recommendations of the Patten Commission for the reform of the Royal Ulster Constabulary.
The Secretary of State is expected to signal his willingness to consider SDLP amendments to the Bill when it reaches its Committee Stage. However, the terms in which he does so - and the nature of any reassurances offered to unionists - will determine how the SDLP and critical Labour backbenchers vote on the principle of the Bill.
Mr Kevin McNamara, a former Labour shadow spokesman on Northern Ireland, has tabled a "reasoned amendment" declaring that the Bill as drafted "does not provide for full democratic accountability, cannot lead to the creation of a police service capable of attracting and sustaining support from the community as a whole, and fails to reflect the determination of the Patten Commission".
It is unclear if Mr McNamara's amendment will be taken. However, the Conservative shadow Northern Ireland Secretary, Mr Andrew Mackay, will divide the House on a separate amendment opposing the Bill because "it fails to preserve the proud title and insignia of the Royal Ulster Constabulary" and permits paramilitary representatives to sit on the policing board and district policing partnerships without a start to decommissioning.
That particular Conservative charge was cast in doubt last night as the spotlight fell on one provision in the Bill which would allow the Secretary of State to remove an independent or political member of the policing board if satisfied that he or she had been convicted of a criminal offence.
A Sinn Fein spokesman told The Irish Times this could create a situation in which Sinn Fein members who would be eligible to serve as ministers in the Executive could be disqualified from the 19-strong policing board, and, as such, was "totally unacceptable".
Two leading Sinn Fein members, Mr Gerry Kelly and Mr Pat Doherty, will continue to lobby against the Police Bill with another Westminster press conference ahead of today's debate. But it will be left to Mr Mallon to carry the nationalist fight on the Commons floor.
In what is likely to be a keynote speech, the SDLP deputy leader is expected to demand radical surgery to the proposed legislation on a wide range of issues, embracing:
The name of the new police service, the emblems to be associated with it, and the flying of the Union flag over police stations.
The new oath of service for police officers, and human rights training.
The power of the Ombudsman to investigate the past conduct of police officers.
Provision for the disbandment of the present full-time Reserve.
Definition in law of the office of the Oversight Commissioner (to oversee the implementation of the reform process).
The composition and staffing of the new policing board.
The power of the policing board to follow up reports from the Chief Constable by initiating inquiries.
Patten stressed the importance of the board's ability to follow up reports by the Chief Constable with inquiries subject to the same national security and other constraints as the report procedure itself. But the SDLP says the Bill gives the Secretary of State the power to prevent an inquiry if he believes it would not be in the interests of the police service.
While Ulster Unionists expect the new title to incorporate the term "RUC", the SDLP is believed to be opposed to the existing reference in the Bill saying that "the body of constables heretofore known as the Royal Ulster Constabulary shall continue in being as the police service".