Leitrim man sentenced to 3 years for violent assault

Dean McTiernan, aged 36, of Riverview Moher, Rooskey, Leitrim, has been sentenced to three years in prison after pleading guilty to a violent assault with a weapon that left his victim, Mr. McDonagh, with serious head injuries. McTiernan was convicted under Section 3 of the Non-Fatal Offences Against the Person Act for the attack.

The court heard that Mr. McDonagh could have sustained more severe injuries had it not been for prompt medical intervention. Judge John Alymer described the assault as being at the upper end of the scale for violent offenses, stating, “This was a very serious assault with a weapon, and the injuries sustained by Mr. McDonagh could have been far worse had it not been for timely medical intervention.”

McTiernan's mental health history was considered during sentencing. Expert evidence from Dr. O'Keefe outlined McTiernan’s struggles with paranoid psychosis and his inconsistent adherence to prescribed medication. However, Dr. O'Keefe assured the court that McTiernan was not considered an imminent danger to himself or others at the time of sentencing. Judge Alymer remarked, “While it is clear that Mr. McTiernan has significant mental health issues, these do not excuse his violent behavior. His mental health history does, however, warrant consideration in the sentencing process.”

The court took McTiernan’s guilty plea into account, which spared the victim the ordeal of a trial. Judge Alymer acknowledged, “I must also note the guilty plea which spared the victim the trauma of a trial. This plea is valuable, though it does not lessen the seriousness of the offense.”

McTiernan was sentenced to three years in prison, with the final 12 months suspended, contingent upon his entering a €100 bond to keep the peace and be of good behaviour for 12 months following his release. He must comply with probation service supervision, attend substance abuse counselling, and follow his mental health treatment plan, which includes outpatient appointments and adherence to prescribed medication. Judge Alymer stated, “The conditions of your sentence are designed to address both your rehabilitation and the need for appropriate punishment. You will need to comply fully with the probation service and your mental health team to avoid further imprisonment.”

McTiernan will receive credit for the time already served in custody. The court also took into account the victim impact statement, which outlined the emotional and physical toll the assault has had on Mr. McDonagh. Judge Alymer concluded, “The impact on the victim is significant, and while the court must consider all factors in sentencing, the seriousness of the offense remains paramount.” The sentencing took place on July 22, 2025.

READ MORE Leitrim man sentenced to 3 years for violent assault