A 21-year-old man who killed his sister with a hammer was found not guilty of murder but guilty of manslaughter by reason of diminished responsibility at the Central Criminal Court yesterday.
Patrick O'Dwyer, then 19, of Shrohill, Ennistymon, Co Clare, had pleaded not guilty to murdering his sister Marguerite (17) at the family home on November 29th, 2004.
O'Dwyer smiled as the verdict was read out, and the O'Dwyer family, who sat beside him throughout the trial, all linked hands.
The jury of six women and six men took 7½ hours to reach its verdict.
Mr Justice Paul Carney remanded O'Dwyer in custody, and adjourned sentencing until a later date.
This is the first time since the introduction of the Criminal Law (Insanity) Act, 2006, that a person accused of murder has proved their responsibility for the killing was substantially diminished due to a mental disorder. Before the new Act no such defence existed, and people suffering from mental disorders were held fully responsible for their crimes.
Defence psychiatrists gave evidence that O'Dwyer suffered from a mental disorder called depersonalisation disorder.
Its symptoms included detachment or estrangement, sensory anaesthesia, lack of effective response and lack of emotional response.
Dr Cleo Van Velsen said she believed O'Dwyer's "emotional autism" and sense of "always being an external observer of himself" led him to self-medicate with alcohol.
Dr Paul O'Connell said depersonalisation was under-recognised, and was only becoming the subject of medical research.
The court heard how Patrick "Pa" O'Dwyer had collapsed on two occasions during his adolescence and that his eyes "rolled" around in his head.
Family members gave evidence that he often went into a "trance" while watching Aertel, and that his attention was easily distracted.
His sister said he would turn his head to the side mid-conversation and mumble. When she would ask him what he had said, he would not know what she was talking about.
As a child O'Dwyer never cried. On one occasion he did not know he had broken his arm until he realised he had lost the use of it.
In the year leading up to the killing O'Dwyer became involved in two violent acts.
On one occasion he became aggressive with his father when he confronted him about his drunken behaviour at a wedding.
On another occasion he punched a woman in the face and bit her fingers when she rejected his drunken attempt to kiss her. She never pressed charges, and he did not remember his actions.
When a false rumour went around the town that he had raped her, O'Dwyer tried to hang himself with a rope.
Dr Van Velsen said she believed O'Dwyer's mental disorder would have driven him to the attention of medics at an earlier stage were it not for the support of his family and tight-knit community.