'No forgiveness': Silver to serve 40 years for murder of Garda Colm Horkan

Stephen Silver, a 46-year-old mechanic from Aughaward, Foxford, County Mayo, has been sentenced to life imprisonment with a minimum non-parole period of 40 years following his conviction for the murder of Detective Garda Colm Horkan at Castlerea, County Roscommon on 17 June 2020. Justice Tara Burns imposed the mandatory sentence at the Central Criminal Court in April 2023 after a jury unanimously found Silver guilty of capital murder following a retrial. The incident occurred when Silver shot Garda Horkan eleven times with the officer's own firearm during a struggle on Castlerea Main Street. Eyewitness testimony placed Silver at the scene, with one observer describing him as appearing agitated immediately after the shooting. Forensic evidence, including a palm print on the firearm, linked Silver directly to the fatal incident. At interview, Silver provided inconsistent accounts to detectives, initially claiming Garda Horkan had discharged the weapon accidentally, later stating he fired only into the air, and subsequently denying he had fired at all. His defence centred on his state of mind at the time, with evidence presented that he had ceased taking medication for bipolar affective disorder approximately nine months prior to the shooting and had not slept for roughly thirty hours before the incident. Although Silver had entered a guilty plea to manslaughter, the jury rejected this lesser plea and convicted him of capital murder, determining he acted with intent to kill. Justice Burns acknowledged the centrality of mental health considerations, emphasising the importance of continued treatment. With standard remission for good behaviour, Silver will become eligible for parole consideration at age 74, after serving approximately thirty years. Members of Garda Horkan's family delivered impact statements in court, expressing their enduring grief and the lasting trauma caused by his death.