The Garda Representative Association has endorsed calls for an inquiry into the murder of a garda in 1970.
The family of garda Richard Fallon is seeking a public inquiry into the circumstances surrounding his murder.
Mr Fallon was killed by armed men during a bank raid on what is now a branch of AIB at Arran Quay in Dublin.
No-one has been held responsible for the murder. Three men were brought to trial and were acquitted.
It is believed that members of a group known as Saor Éire carried out the raid.
In a statement, Mr Fallon's son Finian accused the Government of covering up circumstances surrounding the death of his father.
He called on Minister for Justice Brian Lenihan to initiate an inquiry.
Mr Fallon was married with five children and was awarded the Gold Scott Medal for bravery posthumously.
