He was called to the
Irish Bar in 1805 and practised with great success on the home circuit. He was noted for his mastery of all branches of the Law, and his great powers of mental concentration. Blackburne was nominated a
King's Counsel in 1822, and administered the
Insurrection Act in
Limerick for two years, effectually restoring order in the district. In 1826, he became the
King's Third Serjeant-at-law and in 1830 was advanced to the Second Serjeant. A year later, he was appointed
Attorney-General for Ireland in the
Whig administration of
Earl Grey 'though known to be a tory ... with a view to the Irish administration having a broad political base' and on this occasion was sworn of the
Privy Council of Ireland. He held the post as Attorney-General until 1834; he was readmitted in 1841 and after serving for a year, became
Master of the Rolls in Ireland. As Attorney General he clashed with
Daniel O'Connell, with whom his relations were always bad, when he insisted, against O'Connell's wishes, on the appointment of
Abraham Brewster as
Law Adviser to the Lord Lieutenant of Ireland (in effect, a deputy to Brewster himself). Blackburne's statement that he "would not tolerate a refusal to ratify the appointment", is an indication of the influence which could then be wielded by a strong Attorney General. In 1845, he was chosen as
Chief Justice of the Court of Queen's Bench. Blackburne was appointed
Lord Chancellor of Ireland in February 1852, but was replaced in October. After a break of four years, he became
Lord Justice of Appeal in Chancery in Ireland. In 1858, "he was invited by Lord Derby again to become lord chancellor, but he declined on account of his advanced age and failing health. He changed his mind, however, and decided to accept Derby's offer but was told that the position had been offered to and accepted by
Joseph Napier". He was bitterly disappointed, referring to the decision as "a harsh and cruel blow" and a poor reward for the sacrifices he had made. In 1866, he began a second term as Lord Chancellor, which ended with his death in the next year. Blackburne prosecuted
Daniel O'Connell (who regarded him as a personal enemy) and presided at the trial of
William Smith O'Brien. From 1851, he was
Vice-Chancellor of the University of Dublin. A devoted member of the
Church of Ireland, he opposed any measure hostile to its interests, arguing that an attack on the Church was an attack on the
Union itself. ==Family==