A file with interviews carried out in 1990 by a woman garda with a 12-year-old girl who alleged her father had sexually abused her lay dormant for six years.
Garda Rita Walsh told the Central Criminal Court she found the file in an archive in 1996 when an English police officer telephoned her. She then contacted the girl and her mother.
Garda Walsh, Crumlin, said she had been asked to interview the girl at Our Lady's Hospital for Sick Children. She passed the file on to her superintendent, who has since died, and had no further role as she was not the investigating officer.
She and other colleagues in Crumlin met many alleged victims of sexual abuse because their station was beside the hospital. This offence allegedly happened in another Garda area and it would have been normal practice for her file to be passed on to that area.
Garda Walsh said she next heard about the matter in 1996, when an English police officer telephoned and she found the 1990 file. She and a sergeant began an investigation and she arrested the accused man last August at Heathrow Airport, London, on foot of extradition warrants.
The man had consented to extradition and after he was charged in Dublin District Court he was granted bail, which he had honoured at all times. He had denied the allegations from the start.
It was the third day of the trial of the 51-year-old man, who has pleaded not guilty to eight charges of rape, unlawful carnal knowledge, attempted unlawful carnal knowledge and indecent assaults on his daughter on dates between September 1st 1985, and September 21st 1987, in a west Dublin estate.
The now 21-year-old woman told the jury on the first day of the trial that her father had had sexual intercourse with her almost daily between 1985 and 1987.
The jury heard two English police officers, Det Sgt Nevill Caldercourt and Det Constable Shirley McGlone, tell how the man denied the allegations when they interviewed him on behalf of the gardai. He suggested the allegations were made to hurt him.
Earlier the woman's brother said he had been going through a bad patch in his life in 1994, as he had got involved with the wrong type of peer group.
He asked his father in England if he could go and live with him. He agreed that he wrote to his father saying his mother "has gone weird" and was threatening to throw him out of the house.
Had he known about the sexual assault allegations he would not have asked to live with his father. He had now straightened himself out and was living still with his mother.
The hearing continues before Mr Justice Phillip O'Sullivan.