A Dublin man has been convicted of the armed robbery of a post office in January 2016.

Keith Murtagh (34) of Mariners’ Port, Sheriff Street, Dublin was alleged to have been one of two men who held up the Roebuck post office at Farmhill Road, Goatstown, Dublin on January 5, 2016.

He had pleaded not guilty to robbery of €3,174.54, possession of a shotgun and possession of a shotgun cartridge. His trial at Dublin Circuit Criminal Court heard that his DNA was found on a shotgun cartridge in a car abandoned by the raiders, 400 metres from the post office.

On day ten of the trial, the jury of three men and nine women returned unanimous guilty verdicts on all three charges. Judge Melanie Greally thanked the jurors, who had deliberated for just under four hours.

Dressed in a powder blue suit, a white buttoned-up shirt and a blue navy neck tie, Murtagh did not react when the verdicts were read out by the court registrar.

His lawyer, Garnet Orange SC, told the court that it may be appropriate for a psychological assessment to be carried out and asked for time to allow for this. Judge Greally set a sentence hearing date for October 18 and remanded Murtagh in continuing custody to that date.

The jury heard that on the morning of January 5, 2016, two men arrived at the post office in a blue Subaru Impreza. The men, one armed with a handgun, the other with a shotgun, demanded money and access to the safe.

The raider with the shotgun discharged a shot at the counter in what Dean Kelly BL, prosecuting, told the jury was a violent and frenzied robbery. The raiders, who were wearing track suit bottoms, then used the stolen Impreza as a getaway car.

This car was found abandoned 400m from the raid and Mr Kelly told the jurors they could infer they carried on in another car.

It was the State’s case that a Renault Scenic was linked to the raid. He said a Scenic was seen in convoy with the blue Impreza on the night the Impreza was stolen and a Scenic was seen passing near the post office on the morning of the robbery.

Two nights later, Murtagh was a passenger in a Scenic car with his then partner when the car ran out of petrol on Coliemore Road in Dalkey. Gardaí stopped to assist them and returned with a can of petrol but a routine check found there was a minor road traffic offence outstanding and the car was seized.

Two pairs of tracksuit trousers were subsequently found in the backseat of the car. A forensic analysis of these identified fragments of glass which had the same refractive index as the glass from the post office counter.

A forensic scientist told the trial the glass found and the glass in the post office both had a refractive index which occurs in less than one per cent of glass and was very rare.

The jury also heard that a shotgun cartridge found by investigators in the abandoned Impreza was found to have the defendant’s DNA on it.

Mr Orange said that whoever left the cartridge there wasn’t worried about it being found or linked to them. He said the prosecution case suffered from “confirmation bias” and urged the jury to acquit his client.