Paddy Byrne, who was employed at the time as a gardener at the US Embassy, had just finished work at 5pm on July 22, 1982. He was walking home to the embassy bungalow, where he lived with his wife and children, when he spotted a bearded man slinking from tree to tree towards a parked car. The car, parked on Chesterfield Avenue, belonged to Ms Gargan, who was sunbathing on the grass nearby on what was a scorching summer’s day.
“I saw this guy who was dressed a bit queer, with a hat and heavy pullover on such a hot day,” recalled Paddy yesterday. “I saw him hiding from tree to tree and going towards the car.”
When Ms Gargan went to her car, MacArthur followed and sat in beside her and the two became animated. Paddy first thought he was witnessing nothing more than a lovers’ quarrel, but then he saw something he will never forget.
“He started pulling her hair and began punching her in the side of the head,” said Paddy, who immediately decided to intervene. He thought MacArthur was using his fist but, as it later transpired, he was savagely battering Bridie with a lump hammer.
“I went to the car and hit it a belt with my fist and shouted at him. Ms Gargan was in the back of the car with a newspaper over her and I could hear her crying. He then pulled a gun on me and told me to back off.”
MacArthur got out of the car and lunged at Paddy, threatening him again with the gun — which later turned out to be a replica — before jumping back in and finally driving off.
“The car drove off in a fog of dust,” Paddy told reporter Valerie Cox on the Pat Kenny radio programme.
He then tried to flag down passing cars on Chesterfield Avenue to no avail. “There were no mobile phones in those days and nobody would stop until a colleague spotted me and pulled over.”
The pair gave chase but Ms Gargan’s little grey car had disappeared in the most bizarre circumstances. An ambulance that was passing through the park spotted the car, which had a hospital sticker on the windscreen, and assumed that it was a doctor trying to get a patient to hospital.
Putting on the siren and lights, the ambulance driver acted as escort for the killer and his victim. MacArthur followed the ambulance to St James’s Hospital near Kilmainham but turned around as they entered the hospital grounds and disappeared towards Rialto where Ms Gargan was found a couple of hours later slumped in a laneway. She died four days later in hospital.
More extraordinary events were to follow, leading to the coining of the famous term GUBU (grotesque, unbelievable, bizarre, unprecedented) by then taoiseach Charles Haughey.
Two days later, MacArthur travelled to Edenderry, Co Offaly, to buy a real gun, advertised for sale in a newspaper. On being shown the shotgun, he turned it on its unsuspecting owner, farmer Donal Dunne, and shot him in the face, before stealing his car and driving back to Dublin.
Gardaí launched a huge manhunt and MacArthur was finally arrested on August 13, 1982, at an apartment in Dalkey owned by then Attorney General Patrick Connolly. MacArthur pleaded guilty to the murder of Bridie Gargan and the state dropped charges against him for the murder of Donal Dunne. Given a life sentence, he was released on parole last weekend from the low-security prison Shelton Abbey in Co Wicklow.
Paddy Byrne said yesterday that he is shocked to think that MacArthur is free. “Who is to say that he will not commit another offence?” said Paddy, echoing the concerns of Bridie Gargan’s family.