An Garda Síochána has promised to co-operate fully with a tribunal of inquiry into allegations that a Garda informer was involved in the killings of two senior RUC officers in 1989.
The investigation into the killings of Chief Supt Harry Breen and Supt Robert Buchanan in south Armagh on their way from a meeting in Dundalk was recommended by Canadian judge Peter Cory.
Judge Peter Smithwick has agreed to chair the inquiry and to relinquish his office as president of the District Court and ex officio judge of the Circuit Court, the Minister for Justice Michael McDowell said.
The tribunal will be held under the 1921 Tribunals of Inquiry Act and not under the recently passed Commission of Investigations Act, which allows for faster, cheaper inquiries.
The Minister said the older legislation was being used because the Government accepted Judge Cory's recommendation for a full public inquiry, and not one that could hold some hearings in private.
However, lawyers working on the new inquiry will have their earnings capped, unlike those serving currently on the Moriarty, Mahon and other tribunals.
Senior counsel will be able to earn €213,098 a year or €969 per day, while junior counsel can earn €142,065 a year or €646 per day. Solicitors will be limited to €176,000 a year or €800 per daily appearance, or €100 per hour for work undertaken other than appearing at the tribunal.
The Government is fiercely opposing the British government's attempt to ensure that an inquiry into the killing by loyalist paramilitaries of Belfast solicitor Pat Finucane is restricted.
Judge Cory investigated eight killings in Northern Ireland and the Republic, including those of the RUC men, where security forces were alleged to have co-operated with paramilitaries.
In his report, Judge Cory found that while there was not evidence that a source in the Garda had tipped off the IRA killers, it was necessary for an inquiry to be held to show that such co-operation had not take place.
The allegation that a Dundalk-based garda had tipped off the IRA in south Armagh to the officers' presence emerged shortly after the March 1989 killings.
The two men had travelled to Dundalk in Supt Buchanan's Vauxhall Cavalier car, which he had used over three years to attend cross-Border meetings.
Shortly before he left Armagh, Chief Supt Breen expressed concerns about travelling to Dundalk because he believed that one of the gardaí there was linked to a "notorious" Louth family who were members of the IRA and deeply involved in smuggling.