National court archive ยท 2026-03-23

Man pleads not guilty to murdering grandfather in Donegal Gaeltacht

At a glance

Crime
murdering his grandfather
People
Derek Mulligan, Derek Burns, Patricia McLaughlin SC, Dr Ronan Mullaney, Dr Stephen Monks, Ms Justice Eileen Creedon
Locations
Carrickcoyle, Derrybeg, Gweedore, Co Donegal, Carrickmacafferty, Letterkenny
Court
Central Criminal Court
Outcome
pleaded not guilty by reason of insanity

Summary

Derek Mulligan has pleaded not guilty by reason of insanity to murdering his grandfather Derek Burns in Carrickcoyle, Donegal, in December 2023. Prosecuting counsel told the trial that State and defence psychiatrists agree Mulligan was suffering from a mental disorder when the killing occurred. The trial also concerns alleged property damage, threats and assaults on the same date, and continues before a judge and jury.

Read the original CNI report

Original reporting: courtsnewsireland.ie