Jimmy Guerin defamation case against Gemma O’Doherty proceeds

This report is a localnews.ie summary based on public court reporting and records; sources are listed below.

The Court of Appeal dismissed Gemma O’Doherty’s appeal in Jimmy Guerin’s defamation case on 26 March 2026, leaving it to proceed towards a retrial before a judge and jury. Judge Caroline Costello upheld the High Court’s refusal to strike out the case.

Jimmy Guerin says social media posts and a video published by Gemma O’Doherty in 2019 defamed him by claiming he was a convicted paedophile. O’Doherty maintains she was referring to his brother, Martin Guerin. Martin Guerin pleaded guilty in 2019 to possession of hundreds of images and 146 movie files of child pornography and received a two-and-a-half-year suspended prison sentence.

O’Doherty argued that the case was abusive, bound to fail and an attack on press freedom. The Court of Appeal rejected those arguments, finding valid grounds for the defamation case and no basis to end it before a full hearing. A previous trial collapsed in 2023 after the jury failed to reach a verdict, and a retrial was later ordered.

The judgment criticised false legal authorities in O’Doherty’s AI-assisted submissions and said users should independently verify the accuracy of material they rely on. Judge Costello also said she did not believe O’Doherty intended to mislead the court or was aware that some cited cases were fabricated. The court indicated Jimmy Guerin should be entitled to his legal costs for the appeal.