Background
He was the eldest son of William Hayes of Millmount, County Down.
He was the eldest son of William Hayes of Millmount, County Down.
He was educated at the Belfast Academical Institution, and in 1820 entered Trinity College, Dublin, where he proceeded Bachelor of Arts in 1825, and Bachelor of Laws and Doctor of Laws in 1832.
In 1858 he became Solicitor-General for Ireland. In 1827 he was called to the Irish Bar, and joined the north-eastern circuit, but subsequently transferred himself to the home circuit. Hayes was appointed by the benchers of the King"s Inns as lecturer in constitutional and criminal law.
He was appointed a Queen's Counsel in 1852, and was Law Adviser to the Lord Lieutenant of Ireland under Lord Derby"s first administration, and again in 1858, and was subsequently promoted to be Irish Solicitor-General.
In 1859 he succeeded Philip Cecil Crampton in the Court of Queen"s Bench (Ireland), but was compelled in 1866 to absent himself owing to ill-health. He resigned in Michaelmas term of that year, and died at his house at Bray, County Wicklow, 29 April 1867.
Hayes married, first, Grace Mary Anne, daughter of John Shaw of Donlagh, county Dublin, in 1835, by whom he had nine children. And secondly, Mary Harriett Tranchell, widow of Lieutenant James Shaw, by whom he had one son.