A detective sergeant has told the tribunal he was concerned that interview guidelines were being breached when he heard raised voices coming from an interview room where a woman was being interrogated in 1996.
Det Sgt Sylvester Henry said he brought it to the attention of the custody officer in Letterkenny Garda station who reassured him everything was okay
He said on December 4th, 1996, he was interviewing Charlotte Peoples who had been arrested in connection with the death of cattle-dealer Richie Barron, whom the tribunal has since found was a hit-and-run victim.
Ms Peoples has told the tribunal that she became upset when she heard roaring and shouting from the room next door where her cousin, Róisín McConnell, was also being interrogated.
Det Sgt Henry said he heard raised voices in the room next door. He and another garda reassured Ms Peoples, who became tearful that they would shout at her. He heard the noise for about 20 minutes. He then went out of the interview room and spoke to the custody officer, Garda Martin Leonard.
"I said to him, is everything okay next door and he said 'It is', and I said, 'You sure?' and he said, 'Yeah, yeah, yeah'." Det Sgt Henry said he asked Garda Leonard because "there's a line you don't go over concerning interviewing and I wanted to know whether they were over or under the line."
The chairman, Mr Justice Frederick Morris, asked if he thought the line had been breached. Det Sgt Henry replied: "Damn close to it anyway."
Det Garda John Dooley and Det Sgt John White admitted that they mistreated Ms McConnell and her sister Katrina Brolly during interrogation that day. They were among 12 people arrested in connection with Mr Barron's death. Ms Peoples's husband Michael was arrested the same day. Det Garda Michael Jennings, who interviewed Ms Peoples during another session, said he could not recall her asking him to intervene next door.