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Derek Boyd, who killed sister in 'tragic accident', told gardai he acted in self defence in fatal stabbing
Summary
Derek Boyd, 31, of Scribblestown Place, Finglas, Dublin 11, has pleaded not guilty to murdering Mark Carroll (34) at his home on June 9, 2024. He also pleaded not guilty to making a threat to kill Megan Rock or cause her serious harm, and to assaulting Ms Rock, causing her harm. During his statement, Boyd claimed he acted in self-defence, stating that he believed his life was at risk when Mark Carroll entered his home and refused to leave. He said he grabbed a kitchen knife and warned Carroll not to come closer, but that Carroll lunged at him during a struggle. Boyd claimed he used the knife solely to protect himself. He also mentioned that he had a suspended sentence from a previous conviction for the death of his sister, Sandra Boyd, in a tragic accident in 2022, and that he feared reactivating it. The matter was adjourned for further proceedings. The trial continues tomorrow before Ms Justice Melanie Greally and a jury of seven men and five women.
Who, what, where, when and why
What: Report matter: Derek Boyd, who killed sister in 'tragic accident', told gardai he acted in self defence in fatal stabbing. Charges or matters: murdering Mark Carroll (34) at his home on June 9, 2024. Procedural stage: sentence
When:
- June 9, 2024 Incident
- August 2, 2025 Incident
- August 5, 2025 Other
- March 19, 2022 Other
- June 8, 2024 Incident
- 2026-07-14 Publication
Case subjects
Convicted Person
Charges: murdering Mark Carroll (34) at his home on June 9, 2024 (Alleged Or Contested)
Plea: Not guilty
Outcome: Owing to my suspended sentence still being active, I knew that I couldn't get into a physical altercation as that could have reactivated my suspended sentence". "In an effort to deal with matters", Mr Boyd said he contacted a relative and asked him to come to Scribblestown and "sort out the incident" with the person in question. I also believed that my suspended sentence would be reactivated. "I acted solely to defend myself from what I believed was an immediate and very real threat to my life.
Places mentioned
- at Finglas Garda Station
- same date at Blanchardstown Garda Station
- Blanchardstown
- Scribblestown Place
- Scribblestown Place
Topics
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