He was appointed a Judge of the High Court in 2004. He was chairman of the Referendum Commission for the second Lisbon Treaty referendum in 2009. As a High Court judge he gave a ruling, on the Leas Cross nursing home case against RTÉ, that the public interest justified the broadcasting of material that otherwise would have been protected by the right to privacy. He frequently presided over the Commercial Court during his time at the High Court. He was involved in the establishment of two High Court lists in Cork, Chancery and a Non-Jury List.