Garda Commissioner Drew Harris has apologised to a man wrongly convicted of the manslaughter of a 19-year-old woman in Co Meath in 1971.
Gardaí confirmed that Mr Harris has sent a written apology to Martin Conmey, who was one of three men wrongly accused of killing Una Lynskey.
The teenager disappeared near Ratoath 50 years ago.
Mr Conmey served three years in prison in 1972 following his conviction for manslaughter, but that was quashed in 2010.
The Court of Appeal later ruled in 2014 that Mr Conmey’s conviction was a miscarriage of justice.
The three local men claimed that were subjected to brutal interrogation by some members of An Garda Síochána.
The investigators have long denied these claims.
Mr Harris’ apology comes ahead of an RTÉ documentary about the men’s wrongful convictions and the garda probe of Ms Lynskey’s death.
Mr Harris has also ordered that the Serious Crime Review Team conduct a review of the relevant investigation regarding the suspected murder of Ms Lynskey in October 1971.
A spokesman for An Garda Síochána said: “The outcome of the review will determine whether further action is required from An Garda Síochána.
“In general, in circumstances where a review of an investigation has taken place and this reveals it is appropriate, then an apology to an individual or individuals will be made.
“In relation to Mr Conmey, at the recommendation of the Commissioner of the time and with the agreement of the Minister for Justice of the time, Mr Conmey received a State apology in 2016.”
The spokesman added that Mr Harris has provided Mr Conmey with a written apology from An Garda Síochána in relation to his miscarriage of justice.
The RTÉ documentary, Crimes And Confessions, is a three-part series that examines three miscarriages of justice from the 1970s and 1980s.
Mr Conmey, Dick Donnelly and Martin Kerrigan said they signed forced confessions of the abduction and murder of Ms Lynskey.
Mr Kerrigan was later abducted and killed by Ms Lynskey’s two brothers and cousin.
All three men were convicted of his manslaughter.
Mr Donnelly had his manslaughter conviction overturned on appeal in 1973.
