Aaron Brady has been found guilty of the capital murder of Detective Garda Adrian Donohoe.
A jury convicted him after 20 hours and two minutes of deliberations of shooting the officer during a robbery at Lordship Credit Union on January 25th, 2013.
The 29 year-old of New Road, Crossmaglen, Co Armagh was found guilty by an 11 to 1 majority vote.
The judge thanked the members of the jury and told them the people of Ireland owed them a debt for their service in one of the longest murder trials in the history of the state.
Brady was also convicted of the robbery of €7,000 during the credit union heist.
The jury accepted the prosecution's case that Brady fired a single shot that killed the Garda.
They also had the option of finding him guilty of murder or manslaughter but voted 11 to 1 to convict on count one of Capital Murder.
Brady who pleaded not guilty, displayed no emotion or reaction when the forewoman of the jury read the verdict shortly after noon today.
Outside Court 19 of the Central Criminal Court, Gardai, colleagues, friends and relatives of Det Garda Donohoe wept.
Judge Michael white adjourned the court for 15 minutes after the verdict.
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