After weeks of shocking and often heartbreaking testimony, the jury decided that the defendant was guilty of manslaughter but not of murder. Now it fell to Justice Paul Carney, one of Ireland's most experienced and respected judges, to render an appropriate sentence. To gasps in the courtroom, and loud complaints from relatives of the victim, he announced his decision: the defendant would go to jail for six years.

I'm referring, of course, to the prison sentence given late last year to Padraig Nally, the Mayo farmer who killed John Ward , , a traveller he believed was trying to rob his house , , and not to the four years given to Wayne O'Donoghue for the manslaughter of Robert Holohan.

After an initial flurry of comment and outrage on behalf of Nally, it is the O'Donoghue sentence that has come to dominate public discourse. Having failed to turn Padraig Nally into a national hero for brutally killing Ward, some newspapers, the increasingly loony Sun and Daily Mirror in particular, have now decided that O'Donoghue should be our national villain. The Sun has concluded, against all the evidence, that O'Donoghue is a paedophile and has been making up stories to bolster its case.

For its troubles, it has received a solicitor's letter from its prey, arguing not unreasonably that to be branded a sexual molester of children is a vastly worse thing than to be known as somebody who killed a boy in an incident subsequently described by Judge Carney as close to horseplay.

The Director of Public Prosecutions, James Hamilton, having presumably considered the matter at great length, decided that Padraig Nally's sentence should not be appealed, that six years was an appropriate punishment for shooting Ward in the arm, beating him repeatedly, reloading his gun, chasing his fleeing victim and shooting him to death.

That is Hamilton's prerogative, and I'm not questioning his decision.

However, by opting to prolong the Wayne O'Donoghue trial process by up to a year, and as a consequence hold up the inquest into Robert Holohan's death, Hamilton and his advisers in the DPP's office have thrown up all sorts of uncomfortable questions about their attitude to this case in particular and more generally to the pursuit of justice.

For example, how many years does Hamilton think would be appropriate for Wayne O'Donoghue to serve? Presumably he is not making all this legal effort to get an extra year tacked on to the four already awarded.

He must therefore be thinking about at least two and possibly more. As Hamilton thought six years was appropriate in the Nally case, he is therefore giving the impression that he believes that what Wayne O'Donoghue did was equal to or worse than the premeditated slaughter of John Ward.

Does he actually believe this? If not, why is he appealing Wayne O'Donoghue's sentence? Is it because of what O'Donoghue did immediately after the grim realisation that Robert Holohan was dead? Is Hamilton trying to have that very bad behaviour reflected in a longer sentence? Is he suggesting that Judge Carney wasted an opportunity to do just that when he sentenced Wayne O'Donoghue?

If so why, when he had the chance to do so, did the DPP not bring separate charges against Wayne O'Donoghue for hiding Robert's body, for saying nothing for the best part of two weeks and turning the police search into a charade and a fiasco?

Whatever doubt there might have been about what the jury would decide in relation to manslaughter versus murder, there would surely have been none when it came to deciding whether O'Donoghue was guilty of perverting the course of justice, or wasting police time: they would have found him guilty. But Hamilton decided not to pursue that route and so can hardly get too hot under the collar because Justice Carney attached only a certain amount of weight to it.

Hamilton is appealing the leniency of the sentence, and will therefore seek to paint Judge Carney as somebody who did not properly take into account several issues that arose in the trial including, it is believed, the relative sizes of Robert Holohan and Wayne O'Donoghue.

He could also, I suppose, argue that because Judge Carney implied in court that he was wary of previous occasions when his sentences had been overturned on appeal, his heart wasn't really in the four-year detention he imposed on Wayne O'Donoghue.

That, of course, is idle speculation, the kind of thing that flows from the DPP's policy of not explaining himself. In fairness to Hamilton, he is believed to be reviewing whether there may be circumstances in which he could outline his reasons for making some decisions but in the absence of any explanation of his actions in the Wayne O'Donoghue case, questions will continue to arise.

The DPP has created a stick with which he will be soundly beaten unless he comes up with a series of closely-argued, credible arguments before the Court Of Criminal Appeal.

Failure to make his case and failure to persuade the appeal court judges that they should increase the sentence will lead to accusations that this is a frivolous pursuit of Wayne O'Donoghue and his family, one that has more in common with the unthinking black and white mob justice of the Sun and the Mirror than with the nuanced and balanced approach to its affairs you expect from such an important law officer. I'm sure that's not the case, but we need to hear a lot more about the reasons for this appeal before we can definitively make up our minds.