A university student caused £21,000 damage when he set his neighbours' two cars and house on fire because he believed them to be responsible for the death of a tree in his garden.
The owners were away for the weekend but their son was in a deep sleep in the house and had to be rescued by Dublin Fire Brigade.
Barry McMahon (24), Lower Kilmacud Road, Goatstown, also attempted to set fire to his family doctor's car 10 days later and was caught in a Garda surveillance operation three days later, kneeling at the wheel of the doctor's car.
McMahon, who suffers from a mental condition known as bipolar disorder, claimed that Dr Tiernan Murray had treated his father with a lack of respect during a long illness.
McMahon had completed a degree in agricultural science at UCD and was now engaged in a three-year Ph.D since these incidents, the court heard. He was given a three-year suspended sentence by Judge Desmond Hogan at Dublin Circuit Criminal Court after he pleaded guilty to two counts of arson on May 7th, 2001, and attempted arson and criminal damage on May 17th, 2001.
Dr Connell Larkin, a clinical psychiatrist and director of St John of God Hospital, said McMahon suffered from bipolar disorder since he was 15.
Dr Larkin described sufferers of bipolar disorder as having manic symptoms and they often thought they were God or had to save the world. He said McMahon underwent some manic episodes, fuelled by drink, on the night he set fire to the neighbours' property.
He treated McMahon for over two weeks after the incidents and recommended that he abstain from drinking for five years.
Garda James Mulligan told Ms Una McGurk BL, prosecuting, that a Volkswagen Polo and a Fiat Uno car owned by Martin and Ann Gleeson were both written off, and there was also some damage to the house.
The Gleesons received a High Court injunction against McMahon and he had to stay away from their home. He is living with a relative elsewhere now.
Garda Mulligan said the fire had a devastating effect on the Gleesons but Dr Murray had got on with his life because he was aware of McMahon's illness.
Judge Hogan said at the outset he considered it the type of offence which required a custodial sentence but as the evidence unfolded he had changed his views.
"These most unfortunate events, which could have had much more serious consequences, were due to his illness, and taking that into account it would be unfair to send him to jail," he said.
Judge Hogan said the court should endeavour to create a situation where the two victims should be in a position to continue their lives without the fear of this happening again.
He commended McMahon on his academic achievements to date, in spite of his illness, but ordered that he continue to receive treatment, to obey the terms of the High Court order and forbade him from ever making an application to hold a firearm.
Garda Mulligan said McMahon launched his arson attack on the Gleeson home using a can of petrol and two petrol-soaked rags at the end of sticks after being out drinking on the night of May 7th.
A window in the house, the front door and a canopy caught fire but the emergency services arrived on the scene before it went out of control.
Ten days later, McMahon smashed the front and back windscreens of a car belonging to a doctor who lived across the road and placed a number of fire lighters under the wheels.