Uncle told gardai he strangled his nephew

In his opening speech, prosecuting counsel Michael Durack SC told the jury they must decide whether, at the time of the killing, the accused was of sound or unsound mind.

Mr Durack told the court that the accused lived with his mother Patricia Brennan and sister Barbara, the baby's mother. On 29 February 2000, Barbara put the baby to bed at around 7.30 or 8pm and checked on him around 9pm. Sometime after midnight she noticed that the accused and the child's buggy was missing.

She rang her mother, Patricia Brennan, who had gone out to a friend's house and both women began searching for the accused. The court heard that they found David Brennan at 1.30am. He had clay marks on him. The buggy was found in Carmelite Cottages.

At 10.20am that morning, 1 March, Barbara Brennan realised the baby was not in his cot and she rang the gardai. Gardai found the baby's body lying face down in the water near a disused quarry. The body was trussed with orange nylon rope on which a red brick was attached. Mr Durack said the child was dead before he hit the water.

He said the previous day, Patricia Brennan had taken the accused to StBrigid's Psychiatric Hospital at Ardee where he was attended to by the registrar, Dr M S Das. The accused was unwilling to be admitted and was prescribed medication and advised that he return within a fortnight.

Mr Durack told the jury that this was a "particularly tragic case" in which "the real issue is, at the time when the killing took place, whether David Brennan was sane or insane".

In evidence, Garda John Yorke said he went to Marsh Road, the home of the accused, at around 10.35am on I March, when the gardai were notified of the baby's disappearance.

He said he spoke to David Brennan and asked him where baby Jack was, as the gardai needed to find him quickly. At first there was no response, he just stared blankly ahead and showed no emotion. Then he responded in a low voice "that he was in the quarry", the witness said.

Garda Yorke told the jury that the accused eventually agreed to show gardai where the quarry was but he then refused to get into he squad car. He subsequently agreed to accompany the gardai to the quarry, via McMahon's timber yard. "I then asked him where the baby was," said Garda Yorke. "He pointed to the left towards the viaduct."

"I saw the body of a baby lying face down in the water. He was approximately 12 to 15 feet from the edge of the pond," the witness said. The child's nightclothes were pulled up towards his shoulders and the bottom part pulled down over his buttocks, exposing his back. Gardai later discovered the

child's two blue socks in separate locations on an embankment near the quarry.

Garda Yorke said when the accused was in custody, he told gardai that he had taken baby Jack out of his bed at 12.55am and brought him to the viaduct where he strangled the child and trussed the body up with rope, before tying a brick to the end of the rope and dropping it off the bridge.

Cross examined by defence counsel Sean Moylan SC, Garda Yorke said the accused said "you can't arrest me I did not sign anything. He agreed with the defence that Mr Brennan "didn't seem to understand the seriousness of the offence".

The court heard that the accused was suffering from paranoid delusions and hallucinations. The previous night at 8pm, after he returned from the psychiatric hospital, the accused went into Drogheda Garda Station and told gardai that there had been a murder at the hospital.