Derek Boyd jailed for life for murder of man in Dublin
Alison O’Riordan
Double killer Derek Boyd has been jailed for life for murdering a father-of-four at his north Dublin home and told that his sentence for the manslaughter of his sister four years ago will now be referred back to the Circuit Court.
Boyd (31), who was serving the suspended part of his sentence for killing his sister when he fatally stabbed father-of-four Mark Carroll in the chest, was on Tuesday described by the victim's family as a "monster".
In an emotional victim impact statement delivered to the Central Criminal Court, the deceased's family said that Mark was taken from them in "a vicious and unnecessary act of violence".
The deceased's father, Kevin Carroll, told the court that the family had to go through a "painful and soul-wrenching trial", where they had to listen to evidence of Mark's "sickening injuries".
A Central Criminal Court jury took nearly nine hours last week to find Boyd guilty of murder, unanimously accepting the State's position that self-defence was not open to the accused.
The prosecution had argued that Boyd chose to pick up a knife in "a determined, murderous attack".
In his closing address, Sean Guerin SC, prosecuting, said that Carroll's return to Boyd's home moments after he initially left "wasn't remotely threatening but entirely reasonable", as he was going back to "sort out" an earlier row.
Boyd fled the jurisdiction by boarding a ferry from Belfast to Scotland just hours after he killed Carroll. He had also fled the scene of his sister's killing in March 2022, later telling gardaí he felt ashamed for leaving her like that.
At his sentencing for killing his sister Sandra, the Circuit Court heard that Boyd was assessed as being "at low risk of homicidal reoffending".
In a statement given to gardaí over a year after Carroll's death, Boyd said he believed his life was at risk and that he acted in self-defence when he carried out the fatal stabbing.
The defence said that Carroll had let himself back into Boyd's home after being ordered to leave just minutes beforehand.
Boyd also said that, "given what had happened with his sister", he "did not want to harm anyone intentionally and certainly did not intend to end someone's life".
Boyd took the stand at the trial, telling the jury how he picked up a knife and "begged" Carroll - who he'd been drinking with just moments earlier - to leave his home, claiming that the deceased repeatedly threatened to kill him.
"He told me 'I'll stick the knife up your h*le'", Boyd said of the deceased.
Boyd said that Carroll grabbed him and, during a struggle, tried to take the knife. The defendant said he managed to "break free" and swung the knife at least three times but never intended to kill or seriously injure Carroll.
"Exactly what passed between them in the house was not established on the evidence," Guerin noted on Tuesday.
A pathologist had told the trial that Carroll died from a stab wound to the chest, which measured around 10.5cm in depth and was unsurvivable.
The expert witness also said Carroll had minor injuries consistent with being in a fight.
Handing down the mandatory term of life imprisonment for murder on Tuesday, Judge Melanie Greally said Boyd's sentence was to date from August 5th 2025, when the defendant went into custody.
In relation to the suspended sentence which Boyd was serving for killing his sister when he murdered Carroll, Judge Greally said she would list the case for re-entry before the Circuit Court on Thursday.
Boyd, with an address at Scribblestown Place, Finglas in Dublin 11 had pleaded not guilty to murdering Carroll (34) at his home on June 9th 2024.
In seeking a verdict of manslaughter or an acquittal for his client, Brendan Grehan SC with Seoirse Fennessy BL, defending, had argued that Boyd had "acted out of instinct" when he fatally stabbed Carroll.
Counsel argued Carroll had "trespassed" on Boyd's north Dublin home and that the defendant was entitled to protect himself if he was under attack.
The deceased's partner, Megan Rock, had denied to Boyd's lawyers that her boyfriend had returned to the defendant's house not to make peace, but to "sort out" Boyd.
Carroll had come to garda attention over the years and had pleaded guilty to assault causing harm to his girlfriend Rock in her home, where gardaí noted on arrival that she was bruised, bloody-faced and visibly shaking.
Carroll was also awaiting trial on a second unrelated assault causing harm charge at the time of his death.
Boyd had also pleaded not guilty that on the same occasion he assaulted Rock, causing her harm.
Boyd's girlfriend Chantelle Harcourt (34) had pleaded not guilty to impeding her partner's prosecution, and it was the State's case that she knew some or all of what had occurred that night and avoided telling the truth to gardai in the hours after the fatal stabbing.
The 11 jurors were unable to reach a verdict on either of these two counts on which at least ten of them agreed, and they recorded a disagreement on the remaining two counts on the issue paper.
Guerin said a nolle prosequi would be entered on the count of assault causing harm, meaning that the State would not be proceeding with that charge against Boyd.
Detective Sergeant Niall Murray, of Finglas Garda Station, told Guerin that Carroll was a father-of-four from Finglas but had lived in Ashbourne in Co Meath, as well as in Co Monaghan with his father.
Guerin said Boyd and Carroll were known to each other through a family connection but "not very closely it seems".
The prosecutor said the murder weapon was never recovered and that Boyd told gardai he had taken it with him from the house.
The Det Sgt said Boyd is the only boy in a family of eight children and that he had seven sisters.
The witness said at the time of the murder, Boyd had two children but now had a third child. He said he was not aware of the defendant having any employment history.
The court heard that Boyd has 18 previous convictions, with the most significant being the manslaughter of his sister and the unlawful possession of a semi-automatic pistol at the family home at Collins Place in Finglas, Dublin 11 on March 19th 2022.
Boyd was given a four-year sentence with the final two years suspended for the manslaughter and a concurrent five-year sentence with the final three years suspended for the firearm and ammunition offences. The two-year sentence was backdated to March 21, 2022.
Guerin said today that Sandra Boyd's death had resulted from an accidental discharge of the unlawfully held firearm. He also said Boyd was serving the suspended part of that sentence "at the time of this offence" for the murder of Carroll.
Under cross-examination by Grehan, the officer agreed that Carroll was only out of Scribblestown Place for four minutes - having previously been ordered out by Boyd - when the deceased had returned.
Grehan said it appeared from how the two men were getting on that day and their previous knowledge of each other that the murder was "motiveless".
"Yes, senseless," replied the Det Sgt.
Judge Greally said that this was undoubtedly a "senseless and motiveless" killing. The judge described it as "an act of anger" which has had "the most catastrophic consequences" for all those connected to Carroll.
The judge said she could not imagine how painful it must have been for those close to Carroll to have had to listen to "evidence of his last minutes" during the trial.
Kevin Carroll said he was making the victim impact statement on behalf of the many family members present in court today.
"On June 9, 2024 our family suffered a life-changing loss when we got the news of our son Mark's murder by what can only be described as a monster.
Carroll said the killing had caused their family "psychological stress and pain" and that the suffering had really taken a "toll" on them.
He said Mark's two brothers "have been through hell trying to deal with it" and that it was "a hard pill to swallow" knowing they "will never be able to sit and laugh and joke with Mark".
Carroll said the family had to go through "a painful and soul-wrenching" trial and listen to Mark's "sickening injuries".
He said they had to hear how Mark was taken from them in such "a vicious and unnecessary act of violence". He said they "are broken by the loss of Mark" and their lives have not and never will be the same.
"Mark had four children ..the older kids miss him terribly, and the younger ones will have to be told about their dad...knowing the kids are going to have to grow up without daddy in their day to day lives is heart wrenching".
"Our whole future has been altered, and our way of life will never be the same. Mark's smile and laughter is only a memory now but memories we will cherish forever; but the hurt, the pain, sorrow and grief we will have to live with...But our love we had for Mark and memories will keep us strong as a family.
"There are no words that could explain the hurt and loss and the pain we are all going through. He is missed but never forgotten".
