ON WEDNESDAY afternoon, the clock crept towards four o'clock.

Nobody noticed that the end of the day's hearing was nigh. Everybody in the packed, stuffy Court Number Two was lost in the evidence. All ears were tuned to the clipped tones of Dominic McGinn, prosecuting counsel, as he read the text of a series of e-mails exchanged between a brother and sister three years ago.

The brother was Joe O'Reilly, the man who stands accused of murdering his wife, Rachel, who was bludgeoned to death in her home in The Naul, Co Dublin, on 4 October 2004. O'Reilly denies the charge. The e-mail communication was with his sister Ann and largely concerned a visit to social workers paid by the O'Reilly couple the previous day, 8 June 2004.

Listening to McGinn at the back of the public gallery, Joe's mother, also Ann, kept her gaze straight and unwavering towards the front of the room. She sat alone, surrounded on three sides by elements of the large media contingent who attend daily. She featured in the texts, as a mother who fretted about her adult children, and who expressed concern for the welfare of her grandchildren, the two sons of Joe and Rachel.

"Call her, " Ann wrote to his brother. "She's our mammy and she does really worry about us."

She was also mentioned as the anonymous source who phoned the social services to complain of Rachel's conduct towards the children.

"When Ma reported the incident that brought about yesterday's farce, it very nearly came out as to who did the reporting! ! !" Joe wrote.

In the well of the court, on a bench reserved for the family of victims, the Callaly family listened with increasing distress to the picture the e-mails painted of their sister and daughter, Rachel. The correspondence referred to her twice as a c***. Both correspondents disparaged what they described as Rachel's mothering instincts. "Try a bit harder to talk to her again about her lack of mothering instincts. Have you told her she's none? Does she admit to it?" Ann wrote.

Joe replied: "I keep telling her, straight as you like, exactly what I think of her mothering instincts. Yes. In fact, to be even a little fair, I'm very aware that I'm over critical at times, although I don't feel guilty about it to be honest, as she repulses me."

There were also references to Rachel allegedly manhandling her two sons, and the concern that O'Reilly's siblings felt about the incident.

Visibly upset

Through it all the Callaly family, parents Jim and Rose and their surviving offspring Declan, Paul, Anthony and Ann, listened to this version of their loved one's conduct. When McGinn finished, Rose and Ann Callaly were visibly upset. Their menfolk surrounded them to offer comfort. Ann O'Reilly made her way down through the throngs and out of the court. She has accompanied her son to the Four Courts every one of the 15 days that the trial has lasted so far.

The introduction of the e-mail evidence was dramatic. It provided a view of the relationship between Joe and Rachel O'Reilly which the court had not previously heard. It also brought into stark focus the capacity that technology now affords us to reconstruct the past, something that is vital to the processing of criminal trials.

This type of reconstruction, effectively a snapshot in time, can result in the most private and intimate communications being thrown out into the public domain. Few among us would be comfortable with that level of public scrutiny of our private lives.

Over the last week, the court heard evidence of e-mails, text messages and telephone mailbox message, all of which add to the reconstruction of the months before and after the murder of Rachel O'Reilly.

On Monday and Tuesday the court also heard evidence of telephone contact from Joe O'Reilly's phone on the day of the murder, and the tracking of those calls through the phone company's network of masts.

Traditionally, evidence adduced to get a picture of events surrounding a crime was largely down to written or spoken testimony or, to a much lesser extent, forensics. The testimony would have to be assessed by jurors for veracity or motive. Technology largely does away with those variables, when its retrieval and methodology go uncontested. The O'Reilly murder trial is the first major trial to rely so heavily on modern telecommunications technology.

However, it may not be the full picture. The evidence heard so far is from the prosecution and the defence may wish to present its own interpretation of this hi-tech evidence.

Earlier in the week, another interpretation of the marital relationship was heard in the court.

On the evening of the murder, three gardai visited Joe O'Reilly in his mother's home in Dunleer, Co Louth. They asked Joe to assess his marriage.

"I asked him was he having marital difficultes and was there violence and he said there was no violence, " Detective Sergeant Patrick Marry told the court. He was asked were either of them having an affair, and he said no. Later in the conversation, Sergeant Marry reported, they returned to the subject of affairs.

"There was a short pause in the conversation and Mr O'Reilly said he did have an affair with a girl Nikki Pelley, from Rathfarnham, who worked in Dundrum. He said the affair was over and he didn't want his family to know. He said at 12 o'clock that day he had rung her from his office."

Family life "was suffering"

On the second day of the trial, Rachel's childhood friend was asked whether she knew of any difficulties in the O'Reilly marriage. Jacqui Connor was bridesmaid at the O'Reilly wedding, and godmother to the couple's elder son, Luke.

"Rachel said she wasn't happy, " Connor told the court. "Joe was working a lot, she was on her own a lot of the time. Family life was suffering."

The other woman, Nikki Pelley, gave evidence on Thursday. She told of meeting Joe at a function in The Barge pub in Portobello in January 2004.

They subsequently exchanged jokes by e-mail.

They met up for lunch a few weeks later. Then they went to the cinema together. A sexual relationship developed by April or May.

They met three or four times a week, and O'Reilly would stay over at her house on Tuesdays and Saturdays.

"He had told me they had effectively separated a year and a half before we met, " Pelley testified.

"They had separate bedrooms." Asked how Joe addressed his wife in the wake of marital arguments, she said as "wasp", or sometimes "c***". This wasn't often, she added.

In relation to plans the pair had, she said: "We talked about things, about a future, about being together."

Prosecuting counsel put it to Pelley that she had initially told gardai that she and Joe were involved in an affair, as opposed to a relationship.

"Joe told me he had told the gardai it was this and I should do the same, " she said. "He said if it was a relationship it might be seen as giving him a motive to kill Rachel."

Text messages sent by O'Reilly and retrieved from Pelley's phone were read out in court. At 10.02pm on 16 July that year he sent one that read: "Hey, I want only to be your husband, I know my place."

On 27 July, at 11.51pm: "Sweet dreams too love. Can't even begin to tell you how much I miss and love you, you're everything to me xxx."

On 15 September at 10.33pm: "Ditto my beautiful bride to be."

And on 30 September, five days before the murder, O'Reilly sent a text at 10.09pm. "All your willies tucked up in bed, lights out, missing you. Sweet dreams my darling, love you."

170 witness statements Back in Court Number Two, interest in the trial appears to be increasing the longer it endures.

Some mornings, members of the public begin queuing for entry shortly after 9am. On Wedneday, two women were in situ at 9.25am, perched on a bench that is nominally reserved for the media. Shortly after the official starting time of 11am, a court official instructed them to vacate their coveted positions. They left in search of a seat in the gallery, distraught at their wasted endeavours.

Dozens of the detectives who were involved in the investigation mill around the room, some waiting to be called to give evidence. On the front bench of the public gallery, Rachel's birth mother, Teresa Lowe, and her son, Thomas, attend most days.

As with the Callaly family, the Lowes are accompanied by representatives of victim support organisations.

Joe O'Reilly is immaculately turned out every day in a dark suit, fresh shirt and tie. Each morning he arrives with his mother, usually carrying a folder and large umbrella. He sits at the front on the court, near the witness box, and faces towards the bench.

Frequently, he takes notes, sometimes interacting with his defence team, passing notes to his solicitor. Apart from the first day of the trial, when he broke down as the contents of a letter he had placed in Rachel's coffin were read out, he has remained composed at all times.

As each witness is called, prosecuting counsel Denis Vaughan Buckley calls out the witness number and page in the book of evidence, which contains up to 170 witness statements and reams of technical data.

The court also heard of telecommunication contact between the respective mobile phones of the O'Reilly couple. On the day of the murder, Joe sent his wife at text at 10.07am. He inquired whether she and the boys had got a good night's sleep (Joe left the family home that morning at 5.25am) and said to wish Jacqui (Connor) a happy birthday.

Later that day, after being informed at 1.15pm that Rachel had failed to turn up to collect the couple's youngest son at his creche, Joe made his way out to The Naul. At 1.24pm, he left a message on Rachel's mobile: "Hiya, it's Joe. I've tried you an I don't know how many times now. I'm really, really concerned now. It's not like you, please call me." Twenty minutes later, en route to their home, he tried again: "Me again. I spoke to your mother. I've been crying. You have me worried.

I'm just coming onto the M1 now."

"Sleep well" The last message retrieved from Rachel's phone was left on 4 November, one month after her murder. It was sent at 8.25am that morning.

"Hi Rach, it's me, Joe. I'm very, very sorry for the early morning phone call. This time a month ago you were probably doing what I'm doing now, getting the kids ready for school. Now you're so cold. The sun was out. It was a normal day. You had less than two hours to live.

"I don't want to live without you and that's the truth. I miss you and love you. I just want to go back in time and say I love you. Sleep well and rest in peace. I have to get the boys ready now.

I love you. I miss you. Chat later, bye."

A short day's evidence on Friday was concluded with judge Barry White suggesting to the jury that the prosecution case may now be nearing a conclusion. The defence is expected to open its case sometime next week. The trial continues on Monday.