A French court has found Ian Bailey guilty of the murder of Sophie Toscan du Plantier in West Cork in 1996.
Bailey, 62, was convicted in his absence of killing 39-year-old du Plantier following a trial of only three days after the authorities here twice refused to extradite him.
Presiding judge Frederique Aline listed all the evidence presented to the court during the trial, saying there was "significant evidence" of Bailey's guilt.
She jailed Bailey for 25 years and ordered that a new EU arrest warrant be issued.
Ms du Plantier's battered body was found on an isolated hillside in Toormore, near Schull, west Cork, two days before Christmas in 1996, a Paris court heard.
She was the wife of celebrated cinematographer Daniel Toscan du Plantier.
Bailey, who lived three kilometres from Ms Toscan du Plantier, was arrested twice in connection with the death but was never charged, amid allegations of incompetence and corruption against the local gardaí.
A judge and two professional magistrates heard live evidence from just two Irish witnesses and relied primarily on read statements.
The court repeatedly returned to Ms Farrell's evidence despite her retraction of it and the fact she is considered an unreliable witness by Irish authorities.
Ms Farrell famously stormed out of the 2014 libel case brought by Bailey during cross-examination.
The court in Paris also lingered over accounts describing deep scratches Bailey had to his hands and forehead on December 23, the day Ms Toscan du Plantier's body was found.
Bailey has always said he received the scratches killing and plucking three turkeys and cutting down a Christmas tree the previous day.
But witnesses who watched him play his bodhran with his sleeves rolled up in the Galley pub in Schull on the evening of December 22 said they did not see any scratches.
The court also heard evidence of Bailey's alleged confession to the crime, which he has always denied.
Bill Fuller - one of only two original witnesses to give live evidence - said Bailey had recounted him a scenario of the killing the day after Ms Toscan du Plantier's body was found.
Mr Fuller said Bailey turned to him and said: "You did it ... you saw her in Spar and she got you excited as she walked through the aisles with her tight arse.
"You went to her place to see what you could get, but she wasn't interested so you attacked her. She tried to escape and you ran after her. You threw something at the back of her head and you went further than you planned to."
Mr Fuller believes Bailey was just recounting what had actually happened and switching the perpetrator.
Also examined were Bailey's differing accounts of his movements on the night of the killing.
Bailey first claimed he had spent the entire night at home in bed next to his partner Jules Thomas, but later revealed he had left in the early hours of the morning to walk to his studio about 300m from the house.
He said he had wanted to finish an article.
On Friday morning, public prosecutor Jean-Pierre Bonthoux branded Bailey a "coward" for refusing to face justice and replying only in the media, accusing him of mocking the French court.
He too called on the court to rely on the evidence of Ms Farrell, saying: "There was nothing between her and Mr Bailey, no animosity. She understood (her evidence) was important."
Mr Bonthoux characterised Ms Farrell as a woman who had "had enough" of the effect her evidence had had on her life, saying that was the reason for her decision to stop co-operating.
He also focused on Bailey's performance with his drum in the pub the night before the killing.
"He had his sleeves rolled up, everyone saw his bare arms and no-one remarked on his scratches," he said.
Referring to his alleged confessions, he said each time Bailey avowed the murder he was "in his comfort zone" - either his house or his car - and felt in control of the situation.
Urging the court to convict Bailey and hand him the maximum 30-year prison sentence, he said: "I hope one day as soon as possible to see him in court and see his lawyers defend him."
Manchester-born Bailey had lived in West Cork since the mid-1990s after quitting his career as a journalist and turning his hand to poetry and making ends meet as a gardener.
Despite the scandal caused by the court case, Bailey still lives in the area - running a business selling pizza at local markets with his partner Ms Thomas.
Ms Toscan du Plantier's son Pierre-Louis Baudey-Vignaud, who was 14 when she was killed, has been at the forefront of the family's campaign for justice.
He was seated in the court alongside her parents, brothers and various members of Ms Toscan du Plantier's extended family.
Bailey has branded the case in France a "show trial" and his solicitor, Frank Buttimer, described it as a grotesque miscarriage of justice.
Mr Buttimer said his client is innocent "in this country, in spite of what has been done to him in the other country" and that he would continue to support Bailey.
He told the Press Association: "It is incredibly distressing.
"I do not know how he has managed to survive over the years, this is just the latest, but one of the worst moments of his life, insofar as he has been caught up in this nightmare."