Wednesday 28 October 2026Compiled from published reports. Every claim links to its source.

Ireland Crime

Every case followed from the first report to the sentence, or to where the reporting stopped.

Case No. 0177Murder · Co. Dublin · 29 Jul 2022

David Dunne appeals murder conviction for killing Mountjoy inmate Robert O'Connor

David Dunne, a 42-year-old man, was convicted of murdering Robert O'Connor, a 34-year-old man, at Mountjoy Prison in Dublin on 29 July 2022 after prison officers saw him stamping and kicking the inmate's head. A jury in 2024 took less than three hours to unanimously convict Dunne of murder, with the State Pathologist finding the death was caused by multiple blunt force trauma-type injuries to the head. Dunne, who had 123 prior convictions, appealed to the Court of Appeal, arguing the trial judge's direction on intent was flawed and that a prison officer's testimony was improperly admitted. The three-judge Court of Appeal panel reserved its judgment in October 2026.

  1. Reportednot reported
  2. Arrestednot reported
  3. Chargednot reported
  4. In court9 Oct
  5. Verdict
  6. Sentenced
reportedhappened, not reportedlatest stagenot yet

Key facts

consolidated from all reports
What happened
David Dunne, 42, was convicted of murdering Robert O'Connor, 34, at Mountjoy Prison after prison officers saw him stamping and kicking the inmate's head.
Where
The incident took place at Mountjoy Prison, North Circular Road, Dublin 7.
When
O'Connor was returned to Mountjoy on 27 July 2022 after receiving a prison sentence, the murder occurred on 29 July 2022, and he was pronounced dead on 1 August 2022 after brain stem testing revealed no activity.
Cause
The State Pathologist found O'Connor died from multiple blunt force trauma-type injuries to the head, trunk, legs and arms, with a fractured nose, consistent with punching, kicking or stamping.
Investigation
CCTV showed O'Connor entering Dunne's cell followed by Dunne and three other men, and the prosecution said the evidence suggested an element of coordination between them.
Charges
Dunne was charged with murder.
In court
  • A jury in 2024 took less than three hours to unanimously convict Dunne before trial judge Ms Justice Mary Ellen Ring.
  • Dunne appealed to a three-judge Court of Appeal panel of Ms Justice Nuala Butler, Ms Justice Tara Burns and Mr Justice Paul Burns, arguing the direction on intent was flawed and a prison officer's testimony was improperly admitted.
Other details
  • Dunne had 123 prior convictions and spent much of his childhood in care.
  • Dunne claimed O'Connor punched him twice and he struck back with a rabbit punch, but the prosecution described his account as self-serving and lacking in credibility.
  • The Court of Appeal reserved its judgment in October 2026.
20 statements extracted from the articles
  • whatA jury in 2024 took less than three hours to unanimously convict Dunne. (irishmirror.ie)
  • whatTwo days later, CCTV showed O'Connor entering Dunne's cell followed by Dunne and three other men. (irishmirror.ie)
  • whatA prison officer saw Dunne stamping more than once on O'Connor's head. (irishmirror.ie)
  • whatAnother prison officer saw Dunne kicking the victim in the head. (irishmirror.ie)
  • whenRobert O'Connor received a prison sentence on 27 July 2022 and was returned to Mountjoy that evening. (irishmirror.ie)
  • whenO'Connor was pronounced dead on 1 August when brain stem testing revealed no activity. (irishmirror.ie)
  • causeO'Connor suffered blows to the head causing rotational force that tore nerve cells in his brain. (irishmirror.ie)
  • causeThe State Pathologist said the injuries were consistent with punching, kicking or stamping on the head. (irishmirror.ie)
  • causeDr Mulligan said O'Connor died from multiple blunt force trauma-type injuries with bruises and abrasions on his head, trunk, legs and arms, and a fractured nose. (irishmirror.ie)
  • courtThe appeal was heard by a three-judge Court of Appeal panel of Ms Justice Nuala Butler, Ms Justice Tara Burns and Mr Justice Paul Burns. (irishmirror.ie)
  • courtThe trial judge was Ms Justice Mary Ellen Ring. (irishmirror.ie)
  • courtA prison officer testified at trial despite his statement having been excluded from the book of evidence. (irishmirror.ie)
  • courtThe prosecution said the prison officer was omitted from the book of evidence in error but his evidence was not greatly different from other prison officers. (irishmirror.ie)
  • otherDunne had 123 convictions prior to the murder. (irishmirror.ie)
  • otherDunne spent much of his childhood in care. (irishmirror.ie)
  • otherIn his first garda interview, Dunne read from a prepared statement apologising to the deceased and his family. (irishmirror.ie)
  • otherDunne claimed he just wanted a chat with O'Connor but O'Connor punched him twice, and he struck back with a rabbit punch. (irishmirror.ie)
  • otherThe prosecution described Dunne's account as self-serving and lacking in credibility. (irishmirror.ie)
  • otherThe prosecution accused Dunne of a vicious and unprovoked assault and said CCTV suggested an element of coordination between Dunne and three other prisoners. (irishmirror.ie)
  • otherThe prosecution said the objective reliable evidence showed Dunne lured O'Connor into the cell for the purpose of attacking him. (irishmirror.ie)

The reporting

newest first
  1. 9 Oct2026
    In courtirishmirror.ie, follow-up
    'Institutionalised' criminal appeals conviction for murdering Mountjoy inmate

    Details of the Court of Appeal hearing where Dunne's counsel argued the trial judge's direction on intent was flawed and a prison officer's testimony was improperly admitted, and the prosecution's response. The court reserved judgment.

    victim, Robert O'Connor, 34, male, irish (judged from name)Robert O'Connorconvicted, David Dunne, 42, male, named, irish (judged from name)David Dunne