Jury finds Donegal man not guilty of grandfather’s murder by reason of insanity

Alison O'Riordan

A native Irish speaker who used a granite stone and a cement block while bludgeoning his grandfather to death outside his home in the Donegal Gaeltacht has been found not guilty of murder by reason of insanity by the majority verdict of a Central Criminal Court jury.

The panel accepted the evidence of two psychiatrists that 39-year-old Derek Mulligan was suffering from paranoid schizophrenia when he killed his grandfather and fulfilled the criteria for the special verdict.

Lawyers for Mulligan had submitted that a "just and humane society" seeks not to punish those who are unwell, but to treat them with specialist care, while the State told the jury that there was "convergence of psychiatric opinion" in the case.

Evidence had been given that  Mulligan, who as a child suffered serious sexual abuse at the hands of school caretaker Michael Ferry, told professionals that the paedophile's release from prison had caused him to "spiral".

The trial heard that Ferry was sentenced to 14 years in prison after he was convicted of sexual offending against several boys, including the defendant.

Mulligan (39), with an address at Carrickcoyle, Derrybeg, Gweedore in Co Donegal, had pleaded not guilty by reason of insanity to the murder of his grandfather Derek Burns (78) at Carrickcoyle on December 19th, 2023.

Dr Ronan Mullaney, for the defence, had told the jury that Mulligan was suffering from the mental disorder of paranoid schizophrenia at the time.

He said the defendant would have been unable to know the wrongfulness of his actions and was unable to refrain from committing the act.

Dr Stephen Monks, called by the prosecution, told the jury that the accused was suffering from the severe mental disorder paranoid schizophrenia when he killed his grandfather.

He said by reason of this mental disorder, the defendant did not know the nature and quality of what he was doing, did not know what he was doing was wrong and was unable to refrain from committing the act.

The jury of seven men and five women spent two hours and 22 minutes deliberating on Friday before bringing in majority verdicts on all five counts of not guilty by reason of insanity.

Earlier, the panel handed a note to the trial judge asking how much cannabis was in the defendant's system at the time of his arrest.

They also asked whether these levels had affected his behaviour and whether they could consider verdicts of manslaughter or diminished responsibility.

The trial had heard evidence that Mulligan has a history of substance abuse and at one point was smoking up to €50 worth of cannabis daily.

In reply, Justice Eileen Creedon said the two psychiatrists were aware of cannabis being in Mulligan's system and had taken this into account.

The judge told the jurors that in light of the undisputed facts of the case, they did not have to consider any lesser charge than murder so manslaughter was not available to them.

Justice Creedon further told the jurors that they had not received any evidence of diminished responsibility in the case and that all the evidence supported a verdict of not guilty by reason of insanity.

"As you are aware, your oath or affirmation was to give a true verdict in accordance with the evidence and not to go outside the evidence."

When another note was handed up by the foreman a few minutes later to say the panel were not in a position to reach a unanimous verdict, the judge said she was in a position to give them the option of returning a majority verdict of 11-1 or 10-2.

"Nothing less than 10 will do," she added.

After they had delivered their majority verdicts, Justice Creedon thanked the jury for their consideration of the case, telling them she was conscious of how difficult these cases are.

The judge exempted them from jury service for the next five years.

Prosecution counsel Patricia McLaughlin said there was a bed available immediately for Mr Mulligan at the Central Mental Hospital (CMH) in Portrane.

Ms Justice Creedon then made an order committing Mulligan to the CMH on Friday, with his return before the court scheduled for March 31 next. She also directed the preparation of a psychiatric assessment by an approved medical officer.

Mulligan was also found not guilty by reason of insanity that on December 17th, 2023, at Carrickcoyle, he did without lawful excuse damage property, to wit the windscreen of a Nissan Quashqui belonging to Catherine McDermott, intending to damage such property or being reckless as to whether such property would be damaged.

The defendant was further found not guilty by reason of insanity that on the same occasion he did without lawful excuse make threats to McDermott to kill or cause her serious harm, intending her to believe that these threats be carried out.

In addition, Mulligan was found not guilty by reason of insanity to two counts of assaulting Breege McFadden and Derek McFadden at Carrickmacafferty, Derrybeg in Co Donegal on the same date.

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