The Minister for Justice has apologised to the family of Seamus Ludlow for the way they were treated by organs of the State.
Michael McDowell was speaking to a justice sub-committee which is looking at the Barron Report into the murder of Mr Ludlow.
Mr Ludlow, a 47-year-old single man from Dundalk, was shot dead as he walked home from a pub on 2 May 1976.
The Barron Report into his murder sharply criticised the garda investigation into his death.
The RUC told the gardaí in 1979 that it believed four named loyalists were involved in the killing but this information was not pursued by the gardaí at the time.
The report also concluded that Mr Ludlow had nothing to connect him with any subversive organisations.