Brian Rowan BBC Northern Ireland security editor

Policing has undergone major reform in Northern Ireland

BBC NI security editor Brian Rowan explains why policing in Northern Ireland has become an issue that could make or break a deal to rebuild the ailing political process.

With the Good Friday Agreement and all that has happened since, the face of policing has changed, and changed significantly.

Out went the title of the old force - the Royal Ulster Constabulary - and in came the Police Service of Northern Ireland.

The flag, badge and uniform of the RUC have also gone and there are new ways of recruiting to try to correct the religious imbalance within the service.

There is also a new chief constable, Hugh Orde - an officer who has won significant endorsement from influential Irish-Americans.

The programme of reforms recommended by a commission headed by the former Conservative Party Chairman and Northern Ireland Minister, Chris Patten, was about creating a new beginning to policing and bringing nationalists and republicans on board.

Crucial issues such as plastic bullets, the future of the special branch, and the transfer of powers on policing and justice are the focus of ongoing deliberations Gerry Kelly Sinn Fein policing spokesperson

The SDLP jumped first - taking its seats on the new Policing Board - a watchdog body made up of politicians and independent members - but, up to now, Sinn Fein has refused to endorse the new arrangements.

There is a feeling, however, that republicans are now closer than ever before to biting the policing bullet and that move - maybe more than any other in the history of the peace process - would indicate that the IRA's war is indeed over.

For republicans it is a huge step and, while there are some hopeful signals, there is no guarantee yet that they are prepared to take it.

Some sources believe Sinn Fein may still choose to play the policing issue "long", but they are not ruling out the possibility of a deal in the short term.

One source suggested that might still be possible "if what the IRA is prepared to do is good enough and if the policing signals are good enough."

Much will depend on the assessment made by Gerry Adams and Martin McGuinness at the end of their talks with the British and Irish governments.

But as far as the SDLP is concerned, there should be no more delay.

Hugh Orde has been endorsed by influential Irish-Americans

A senior party source told BBC News Online:"The major changes to policing in law and practice, driven by the SDLP over the past 18 months, means there are no more excuses not to make the jump."

But Sinn Fein's Gerry Kelly responded: "You would expect the SDLP to say this.

"They jumped too soon. Had they held their nerve on policing we would have achieved much more by now on this issue."

Sinn Fein will not be pressurised or rushed and senior party figures had more talks with British officials in London on Tuesday.

UK Prime Minister Tony Blair wants to see "acts of completion" involving a range of parties.

Mr Blair has signalled that only truly significant moves would create enough confidence to restore the power-sharing institutions at Stormont.

The devolved institutions were suspended last October amid allegations of IRA intelligence gathering at the very heart of government in Northern Ireland.

As part of a deal that is being pieced together, there will be radical security changes.

'Acts of completion'

A demilitarisation programme, with an end point in 2005, will slash troop numbers here to 5,000 and close all but 14 army bases.

The British Government will make a commitment to transfer policing and justice powers to politicians in Northern Ireland, and a judicial process will be used to settle the controversial issue of on-the-run paramilitaries, suspects still wanted by the police.

The proposed Judicial Commission will have powers to free suspects on licence, but no one goes to jail.

All of these matters are hugely difficult for unionists, who still don't know what the IRA is prepared to do by way of its "acts of completion".

The republican movement will not decide until it has heard the Adams and McGuinness assessment of the continuing negotiations.

They are still stressing the importance of the policing issue.

However, progress has been made.

The Sinn Fein leadership will not be rushed into a decision

In the context of an overall deal, ex-prisoners will be allowed to sit on new District Policing Partnerships, and in Belfast the partnership will have four sub groups in the north, south, east and west of the city.

Sinn Fein has also secured legislative change which will require the Northern Ireland Secretary of State to consult more widely before issuing or revising codes of practice for the police or long term objectives for the service.

That consultative process will now involve not just the chief constable and the policing board but the Police Ombudsman, the Northern Ireland Human Rights Commission and the Equality Commission.

An SDLP source told BBC News Online:"After 18 months of saying so much was wrong with the law on policing, Sinn Fein have now got one change to the law on policing...so much delay for so little."

But Sinn Fein will measure progress not just in the legislation, but on amendments to what is called the "Implementation Plan" - the document which spells out what will happen and when in terms of the Patten reforms.

Gerry Kelly told News Online: "Sinn Fein welcomes the introduction of the proposed amending legislation on policing .

"These are important matters but they are not the only issues which Sinn Fein has pressed the British Government on in recent negotiations.

"Crucial issues such as plastic bullets, the future of the special branch, representativeness within the police service and the transfer of powers on policing and justice are the focus of ongoing deliberations between Sinn Fein and the British Government."

So the talking continues but decision time is not far away and in terms of making a judgement, there has never been a tougher call for Adams and McGuinness.