Gardaí are to be given the authority to participate in a Belfast inquest into the deaths of 10 Protestant men in the Kingsmill massacre in south Armagh in 1976.
Minister for Justice Charlie Flanagan is to seek Cabinet approval on Tuesday to allow for greater co-operation between the Police Service of Northern Ireland (PSNI) and An Garda Síochána.
The Criminal International Co-operation Bill will give the Garda Commissioner the authority to enter agreements with enforcement bodies outside the State.
Government figures say this will allow for gardaí to assist with official inquiries into the Kingsmill ambush.
The massacre took place on January 5th, 1976 near the village of Kingsmill. Gunmen stopped a minibus carrying 11 Protestant workmen, lined them up alongside it and shot them. Only one victim survived, despite having been shot 18 times
The Historical Enquiries Team found the Provisional IRA was behind the atrocity but it never admitted responsibility. At a hearing last September, an inquest heard from the coroner about difficulties in accessing material from the Republic of Ireland.
The new legislation would allow for a member of the Garda to give evidence to the inquest, if necessary.