Four loyalists suspected of killing a County Louth forestry worker almost 30 years ago have been named in a Dublin judicial report about his murder.
Mr Justice Barron criticised the 1976 murder investigation
The report's author, Mr Justice Barron, criticised the Garda investigation into the murder near Dundalk in May 1976.
He said Gardai failed to question four suspects named in the report because the RUC might have demanded reciprocal rights in the Irish Republic.
Seamus Ludlow's family have claimed collusion on both sides of the border.
They have maintained there was a cover-up following the murder.
Last month's inquest into the 47-year-old's killing was told that in 1998, the RUC arrested and questioned four men.
Two of them independently gave evidence of how and where the murder was committed.
However, the Director of Public Prosecutions in Northern Ireland decided not to press charges.
The inquest was also told that in 1979, Irish police had the names and addresses of the same four men but Garda Headquarters did not allow the investigating officers to proceed.
Mr Justice Barron, a retired judge, said it was important to view these matters in the context that the period between 1976-1980 was "one of huge turmoil".
"Deep divisions and distrust existed, not only between the nationalist and unionist communities in Northern Ireland, but also between the governments of the United Kingdom and this (Irish) state," he said.