Ian Bailey confirmed he was taken to a Cork Garda station having failed a roadside breathalyser test only to subsequently pass an electronic sample test.
Mr Bailey (62) issued a statement following media reports he had been taken to Bantry garda station, west Cork, on Sunday evening for suspected drink driving.
The Manchester-born journalist - who was prosecuted earlier this year by the French authorities over the death of Sophie Toscan du Plantier (39) in December 1996 - said he had passed a follow-up electronic sample test.
"I can confirm that on Sunday evening last, I was stopped at a Garda checkpoint outside Schull," Mr Bailey said. "I failed a roadside breathalyser test.
"At that point, I was taken to Bantry garda station where I subsequently passed the electronic test. The treatment by gardaí towards me was courteous at all times," he added. He declined to comment further.
The incident occurred at around 9pm. Mr Bailey left the Garda station to return home at around 10.30pm.
Mr Bailey has lived in west Cork with his partner, Welsh artist Jules Thomas, for almost 30 years.
He sued the State for wrongful arrest after claiming his life had been destroyed through the wrongful association with the du Plantier murder investigation. In 2003, he mounted a high-profile series of defamation actions against Irish and UK newspapers over their coverage of the du Plantier case.
He also lodged a formal complaint with the Garda Síochána Ombudsman Commission over his alleged treatment.
Mr Bailey said "sinister attempts" were made to frame him for the crime.
The French mother of one was found beaten to death by her isolated holiday home outside Toormore on December 23, 1996. Ms du Plantier had suffered a brutal attack.
Mr Bailey was arrested for questioning by gardaí during their investigation in 1997 and 1998. He was released without charge on both occasions.
The Director of Public Prosecutions later ruled out any prosecution in Ireland over the killing.
However, following a lengthy investigation launched in France under Magistrate Patrick Gachon in 2007, Mr Bailey was tried in absentia before a Paris court last May.