On the day of the murder Rachel O'Reilly dropped her son Adam to school in Hedgestown National School and her other son Luke to Tot's Utd crèche. CCTV images of her Renault Scenic car captured her leaving at 9.03am.
At 9.10am, Mr O'Reilly's Fiat Marea estate was seen going past the quarry towards the house.
Mr O'Reilly, an operations manager in the outdoor advertising company, Viacom, claimed he was inspecting posters 25kms away in the Broadstone Phibsboro bus garages.
At 9.41am, Rachel's car was seen returning from the school run. 18 minutes later, at Mr O'Reilly's car was seen travelling away from the house.
During that 18 minute period, Mr O'Reilly beat his wife Rachel to death in her bedroom.
Car keys found under her body show she must have just been inside the house when he attacked her. The floor was blood-soaked and even the walls and ceilings were bloodstained. However, there were no blood drippings anywhere else, suggesting Mr O'Reilly, would have been drenched in blood, must have had a shower.
State Pathologist Dr Marie Cassidy said she could not tell the exact time of death and that Rachel could have "could have lain unconscious for some hours prior to her dying." However, she estimated the time of death as being anytime from between 9am and 3pm.
The cause of death was a fractured skull or "blunt force trauma " to the head. She said Rachel sustained up to 9 blows to the head with an object and that she could have been standing upright when she struck initially.
For the remainder of the blows, Rachel must have been on the ground. However, she said the head injuries would not have caused immediate death but rather render her unconscious and "while unconscious she would have inhaled blood".
Dr Cassidy also said that Rachel, who was athletic, tall and strong, "appeared to have made some attempt to defend herself" as there were self-defence type injuries to her arms.
It was Rachel's mother, Ann Callaly who would later find her dead daughter's body lying in a pool of blood.
The alarm was raised when Rachel failed to pick Luke up from crèche. After Montessori school teacher Helen Moore failed to get in touch with Mrs O'Reilly, she rang Mr O'Reilly, who then contacted Rachel's youngest brother, Anthony Callaly to ask whether Rachel was there.
Anthony Callaly told the court that that he'd spent that morning painting the house with his father and that he'd been having lunch when Mr O'Reilly, with whom he got on well, rang to see whether Rachel was there, as she'd failed to collect Adam from crèche. He said they were all 'immediately suspicious.' "She lived for her kids. It was very out of the ordinary," he explained.
When Rachel's mother, Rose Callaly, couldn't get through to her, she found the fact that she hadn't collected Adam so 'unusual' that she immediately drove to her daughter's house to find out what was going on. This was at 1.20pm.
In the meantime, Jimmy Callaly rang one of Rachel's neighbours to ask her to go over to the house and check on Rachel. But when Mrs Callaly phoned from the murder scene in an "extremely distressed" state, telling them she thought Rachel was dead, Mr Callaly left immediately and his sons followed.
In her evidence, Mrs Callaly said the first thing she noticed when she arrived at the house was that the dogs would not follow her into the house as they usually would. She then went around the back as normal to enter the house through the patio doors, which were open. She then realised the curtains, which were always open, were closed on this occasion.
She said the kitchen tap was running 'quite strongly' and that folded clothes looked like they had been moved from the table to the floor. After that, she described walking through the house, calling Rachel's name. As she went along, she noticed doors of a china cabinet were open and said it was then that she became uneasy. When she looked into her daughter's room, she noticed her body lying on the floor. "As soon as I saw her I knew she was dead and that she had been murdered," she said.
She added: "I knelt down beside her and Iremember talking to her and I remember rubbing her arms. They were cold. I knew she was dead." Others began to arrive on the scene shortly afterwards.
She said that Joe O'Reilly ran into the house, and got down on his knees beside the body. She said: "His first words were, Jesus, Rachel, what have you done?" She added: "Even at the time I thought this was bizaare." The scene needed to be preserved and after everyone was asked to leave the house, Mr O'Reilly approached Gda Thomas Cleary and apologised for having destroyed forensic evidence. "I'm really sorry, I'm probably after ruining it on you," he said.
The day after the murder, a satchel and a camera bag were found on the side of the road close to the O'Reilly household. But €450 in Mrs O'Reilly's purse was not taken, nor was the jar in the utility room which contained €860 cash.