Courts / Donegal / Report

Native Irish speaker found not guilty of murdering grandfather by reason of insanity

Summary

A native Irish speaker, 39-year-old Derek Mulligan, has been found not guilty of murdering his grandfather by reason of insanity following a majority verdict by a Central Criminal Court jury. The jury accepted the evidence of two psychiatrists who testified that Mulligan was suffering from paranoid schizophrenia at the time of the incident. Mulligan had pleaded not guilty by reason of insanity to the murder of his grandfather, Derek Burns, who died from severe injuries sustained on December 19, 2023. The court also heard that Mulligan was found not guilty by reason of insanity on additional charges, including damaging property, making threats, and assaulting two individuals. The trial revealed that Mulligan had a history of mental health issues and had experienced significant trauma, including sexual abuse in his childhood. The court ordered Mulligan's commitment to the Central Mental Hospital for psychiatric assessment, with a return date scheduled for March 31. The judge exempted the jury from service for the next five years due to the difficulty of the case.

Who, what, where, when and why

What: Report matter: Native Irish speaker found not guilty of murdering grandfather by reason of insanity. Charges or matters: sexual offending against several boys, including the defendant. Procedural stage: sentence. Findings: Acquitted

When:

• December 19, 2023 Other
• March 31 Hearing Or Sentence
• December 17, 2023 Hearing Or Sentence
• December 17 Incident
• December 19 Other
• 2026-03-27 Publication

Why: Mr Mulligan reported it to gardai in 2011 when he was aged 22 but wasn't prepared to go through with the court process because of the harm the first case had caused him, resulting in the second case collapsing. CNI source report

Case subjects

Places mentioned

Topics

Stage Sentence Violent Crime

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Read the original CNI report