With that, the jury filed out, their task made redundant, and justice was put on hold for another day.

The collapse of the murder trial of Dublin man John O'Neill last Wednesday was unique on two fronts. The premise for the collapse was unprecedented. Carney said he couldn't rule on a submission by the defence counsel that the prosecuting barrister, Gerard Clarke, had been "grossly misleading and defamatory" in his closing speeches. The reason Carney couldn't rule, he said, was that he didn't properly hear Clarke's speech. There was "quite a bit of muttering as far as I am concerned and I have to discharge the jury on that account", he said.

The three-day trial was aborted.

O'Neill and relatives of the deceased, Rosemary Dowling, will have to put their lives on hold again until the new trial. Further cost to the state will accrue. And Clarke has been subjected to an effective rebuke from the bench that could affect his career, whether or not the accusation that he didn't deliver his address properly is justified.

The judge did not say why he didn't intervene during the address to ask Clarke to speak up. The jury foreman did not request that he do so, and juries are generally not shy in asking barristers or witnesses to pump up the volume. Neither is it clear whether the judge would have taken action himself to stop the trial if defence counsel Brendan Grehan hadn't intervened with an objection, which itself had nothing to do with the volume of Clarke's delivery.

Discharging juries The other unique aspect of the collapse has to do with Carney's oftenstated reluctance to discharge juries and therefore abort trials. The discharge of juries has become increasingly common in criminal trials.

For what often appear the most innocuous reasons, barristers call for a discharge because a client, usually the defendant, has suffered prejudice in the eyes of a jury.

Carney resists these attempts in nearly all cases. As he pointed out at a recent conference: "I will only discharge a jury in the most exceptional circumstances. . . I suppose the most frequent reason for discharge is that someone has blurted out that the accused is in some form of custody. So what? Who is being fooled for a moment by the television pictures of the accused being towered over by two burly prison warders with the handcuffs barely below the radar?"

Yet, on Wednesday, he discharged a jury on what appear to be grounds that were hardly exceptional and could perhaps have been rectified by a reading of the transcript.

The incident generated much talk in the Four Courts last week, but every theory came with the rider that Carney is an exceptional judge, working in very difficult circumstances.

As the presiding judge in the Central Criminal Court, his working day is filled with murder, rape and examples of some of the most depraved behaviour of which human beings are capable. He has more than once described the defence mechanism he employs to ensure his every waking moment isn't filled with images of horror.

"By 4.10 each afternoon, I have completely forgotten what has happened in my court that day and even who the counsel were. This is a necessary defence mechanism to have in a court where jurisdiction is largely murder and rape, and if I did not have this facility, my mind would constantly be cluttered with images of semen and body parts, " he told the recent conference.

On the administrative side of his brief, he has reduced the waiting time for murder trials from nearly two years to under four months.

He has also overseen the sitting of the court in regional outposts such as Limerick, Cork and Castlebar, far from the Four Courts, which he refers to as "the mother ship". On the bench, he has overseen most of the high-profile murder cases that have come before the court since his appointment in 1991.

Awareness of victims' plight During proceedings, he looks out into the well of the court, rarely regarding the counsel or witnesses who are speaking. Neither does he take the copious notes that some of his colleagues find helpful in their deliberations.

With a mouth that curls down at the end, Carney projects a countenance that might charitably be described as grumpy. But he has demonstrated an acute awareness of the plight of victims of crime, which has been recognised by victim support groups.

Among the more high-profile killings he tried was that of John Ward by farmer Padraig Nally in 2004. The fallout from that trial brought him more trouble last Thursday when the Court of Criminal Appeal (CCA) overturned Nally's conviction for manslaughter and ordered a retrial. That, coupled with Monday's ruling by the court to increase a rapist's sentence imposed by Carney from six to nine years, made it a bad week all round at the office for the 62year-old judge.

He is extremely sensitive about the tampering with his sentences by the appeal court. On the grounds of professional pride, he regularly expresses annoyance that the court adjusts his sentences, despite his forensic interpretation of guidelines handed down by the court.

In 2004, in relation to a serious rape conviction, he said the CCA had "repeatedly set aside any non-mandatory life sentences imposed by me, so that I have just about thrown my hat at it". While the appeal court didn't change his life sentence in that instance, one of the three judges, Nial Fennelly, said Carney had "expressed concern about inconsistent jurisprudence of this court", which he said was "most undesirable to add to any such confusion". The rebuke didn't stop Carney expressing his frustration at the court, which he does on a regular basis.

Enjoying the limelight He did it again last January when sentencing Wayne O'Donoghue for the manslaughter of 11-year-old Robert Holohan. Carney noted that the CCA had previously "decimated" the sentences he and colleagues had handed down for manslaughter. Some interpreted this remark as constructing a bulwark against the media backlash that he must have known would follow the sentence of four years.

He is known to enjoy the limelight afforded by his comments, and he has facilitated the media where possible, such as at the beginning of the O'Donoghue trial when TV cameras were allowed to film the courtroom.

He is one of the few judges to have expressed no opposition to the principle of broadcasting trials and he has invited reporters to his chambers on social occasions.

But he has also hit out at coverage he regards as inaccurate or unfair. He got an early taste of the lash of the red-tops when, in high-profile rape cases in 1992 and 1993, he gave respectively a suspended sentence and a seven-year sentence, both of which were decried as excessively lenient.

Under severe pressure at the time, he was involved in an after-hours incident at Dublin's Shelbourne Hotel.

Later, he threatened contempt of court on any media outlet that misrepresented a particular sentence.

The incident instructed him on how headlines, rather than detail and legal principles, can dominate public discourse.

A former election agent of Michael McDowell, he has often been touted as being in line for promotion to the Supreme Court. But whether by choice or the belief that he is too valuable to the system in his current position, he has stayed put.

This week, the CCA will rule on an appeal by the DPP in the O'Donoghue case against the leniency of Carney's sentence. More headlines are guaranteed, whether good, bad or indifferent. The nature of the job and his own disposition ensure that it will ever be thus, as long as he is a judge of the Central Criminal Court. Wayne O'Donoghue: sentenced by Carney last January CLOSING ARGUMENTS IN O'NEILL TRIAL GERARD CLARKE SC "Unfortunately the only account of what happened is the version of events given by Mr O'Neill to the guards.

Rosemary Dowling is dead. She can't tell you what happened, what it felt like to have the first blow of the lump hammer on her head, the second, the third.

"What it felt like to have her brain damaged, whether she was conscious or not when the blade went into her neck.

She has no voice in this case but in a way, ladies and gentlemen, you can be her voice and if she could speak now she would say, 'John O'Neill murdered me.'" BRENDAN GREHAN SC Grehan told the jury that Clarke had entertained them with his closing speech but said he had invited them to speculate, and where Clarke had no evidence he suggested to them that they should take the ball and run with it.

He said he had never heard of such a thing before and this kind of "impassioned" plea should not be allowed to go to the jury. He said the prosecution had irresponsibly asked them to bring "emotional baggage" to their deliberations in the case.