Haunting reminders of missing Amy throughout stepdad's trial
Manslaughter verdict as Mahon is cleared of murder
The unsolved mystery surrounding missing teenager Amy Fitzpatrick loomed large over her stepfather Dave Mahon's murder trial.
Although five years and almost 3,000 kilometres separated her disappearance and the death of her brother Dean, the two events seemed inextricably linked.
The trial would hear the relationship between Mahon and Dean Fitzpatrick was an extremely volatile one.
The tensions between the pair came against the backdrop of a family mentally and financially scarred by 15-year-old Amy's unexplained disappearance.
Mahon always maintained he had not meant to kill Dean during a confrontation outside his north Dublin apartment on May 26, 2013.
Dean had mental health and substance abuse issues, with medical files revealing he self-harmed and had feelings of guilt over Amy's disappearance.
The main theory put forward by the defence was that the young man had been suicidal and deliberately walked into a knife Mahon was holding.
A jury ultimately found - in a majority verdict of 10 to 2 - that Mahon had not intended to kill Dean (23), but was guilty of manslaughter.
Amy's disappearance came to the fore from the outset of the trial.
Prosecution counsel Remy Farrell said Mahon had been "very much in the limelight" since Amy vanished near the Spanish resort of Fuengirola eight years ago. When news broke that Amy's older brother Dean had died violently five years later, the public needed no introduction to the family.
Dean's mother Audrey and his stepfather had waged a long and very public campaign to find out what happened to the teenager.
Audrey was rarely seen without Mahon at her side. She stood by him after he was charged with Dean's murder and the couple were married last year. She supported him in court throughout his nine-day trial.
Originally from Donaghmede in north Dublin, the children had moved to Spain with their mother and Mahon in 2004. They lived in a secure gated housing development, with Mahon working as an estate agent and his partner in the pub trade.
Amy was last seen walking home from a friend's house at about 10pm on New Year's Day 2008. She is thought to have taken a short cut up a dirt lane when she vanished without a trace.
The couple's efforts to find out what happened to Amy were beset by questions over the teenager's lifestyle, amid reports she hadn't been attending school and had been seen out late at night in local bars and nightclubs.
The search for answers was costly and led to the couple returning home. Mahon would tell gardaí they had a great life there "with eight or nine houses and bars".
"We were millionaires really, but spent it all looking for Amy," he said.
Dean returned to Ireland a year after his sister's disappearance and lived with his birth father, Christopher, for a period. He began a relationship and became a father. But he was a troubled young man, taking drugs and self harming.
A seemingly innocuous row with Mahon precipitated the young man's violent death. Both men were members of the Northwood Gym in Santry and Dean interfered with Mahon's bicycle outside the gym. After discovering this, Mahon phoned Dean and asked him to come over. A friend testified Mahon was drunk and agitated.
Fitzpatrick admitted messing with the bicycle to annoy Mahon.
He got up and left and Mahon followed him. The only account of what happened in the following minutes was provided by Mahon.
He claimed his stepson had taken a knife from the kitchen and pulled it on him. "I took it off him. I put it into my back pocket," he told gardaí.
But for some reason Mahon took the knife out his pocket and held it in his hand. He said he asked Dean why he had pulled the knife on him.
"And he walked into the knife. He was putting it up to me and he walked into the knife," Mahon told detectives.
"Is it an accident or murder? I don't know, but it's my fault," he said.
Mr Farrell said Dean had been "gutted".
Evidence was heard that Mahon had earlier threatened to stab Dean's girlfriend when she refused to phone her boyfriend for him.
The court was also told Mahon later threw the knife Dean was stabbed with out of a car window.
Mr Farrell remarked this behaviour was right out of the "how to get away with murder handbook".
However, evidence given by Deputy State Pathologist Michael Curtis weakened the prosecution case.
Contrary to prosecution claims, he did not consider the stabbing to be a gutting. Crucially, he also testified that the 14.5cm-deep stab wound had tracked backwards and traversed muscle "with a horizontal slice".
He said that it would be more likely to be deliberate if the wound tracked steeply upwards or steeply downwards.
But it had tracked only slightly upwards.
Dr Curtis also said it was not possible to determine whether Mahon had deliberately thrust the knife into his stepson or if Dean had "run on" to the knife.