For the McLaughlins, the tipping point came just after 3.30pm. It had been a long, draining day at the end of a punishing week, and an afternoon given over to evidence on the elasticity and stress points of Dyson vacuum cleaner cords was easing mercifully towards a close.
With 30 minutes left before the usual finishing time, Mr Justice White asked the jury if it would be willing to stay on a little to hear evidence from State Pathologist Prof Marie Cassidy, who had been waiting her turn since morning.
Prof Cassidy took the stand. Speaking clearly and purposefully, her observations came rapidly. Height: 5ft 3in. Slim build. Weight: 54kg. Medium-length blonde hair. Teeth: natural. Ears: pierced. Toe-nails: painted. Feet: bare.
Brighid McLaughlin's lip quivered. Her father, Owen, bowed his head and stared at his feet. So fast did the words drift out into the court that few could have caught them all; instead, vague fragments hung in the air.
"A ligature mark . . . an irregular graze of 2.5 x 0.4cm . . . a transverse linear mark . . . a blanched furrow . . . Two superior horns fractured . . . Two dark parchmented abrasions . . . Pin-point haemorrhages . . ."
On it went. As Prof Cassidy described a mark that crossed Siobhán Kearney's thrice- fractured Adam's apple, she motioned her left forefinger across her neck. As she did so, Owen McLaughlin recoiled sharply in his seat. Aisling, pushing tears from her eye, gripped his hand in hers.
But worse was to come. Without warning, Dr Cassidy raised a close-up photograph of Siobhán's face so that the jury could see the marks she was describing. It was there for all to see. In the third row, the dead woman's parents and siblings dropped their heads as one.
Deirdre, her mother, mouthed a few words. One of the detectives glanced anxiously over his shoulder towards the family, just as Brighid and Aisling broke into tears.
Just over Prof Cassidy's left shoulder, Brian Kearney had drawn a hand over his mouth.
In her evidence, Prof Cassidy said she believed Siobhán Kearney died due to ligature strangulation from compression of the neck. Her injuries were consistent with a significant force being applied to her neck and maintained for enough time to cause death by asphyxia.
"One hypothesis is that she could have been assaulted in the bed and gripped around the neck and rendered unconscious, at which point a ligature could have been wrapped around her neck, accelerating her death."
However, Prof Cassidy told defence counsel Patrick Gageby that while it was uncommon to see injuries of Siobhán's type in low-level or high-level hanging, it was not out of the question.
Earlier, the court had heard from Neal Murphy, an engineering lecturer at UCD, who showed that the vacuum cleaner flex found around Ms Kearney's body could not have held her weight for more than five to seven seconds.
Much discussion centred on the door of Siobhán Kearney's en-suite bathroom, which was removed from its protective sheeting and displayed in court yesterday. For a few hours, the white door stood incongruously in the oak-panelled courtroom, propped up by two wooden grooves just in front of the accused. It brought with it an odd, unsettling immediacy.
For what felt like an infinity, forensic scientist Dr Michael Norton teased out the lengths, stress points and loop permutations of the Dyson flex draped over the frameless door.
At one point, as he grappled unsurely with the latest jumble of loops and cross-overs, knotting and reknotting, he paused for a second. "I'm getting myself tied up in knots," he said, leaving the rare sight of smiles in the courtroom.
But the McLaughlins didn't smile. Brighid, her hands linked as if in prayer, kept her eyes trained hard on the white door in the corner.
