He was born in County Cork, the fourth son of Nicholas Pyne of Monageely. He matriculated from Queen's College, Oxford in 1662, was called to the English Bar in 1669 and to the Irish Bar in 1674. In 1686 he became counsel to the Irish Revenue Commissioners. Although he was willing to accept preferment under the Roman Catholic King James II, he was a strong Protestant, and a Whig in politics, and was later a supporter of the Revolution of 1688.
After the Battle of the Boyne in 1690, he was appointed joint Commissioner of the Great Seal of Ireland with Sir Richard Ryves and Sir Robert Rochfort. Early in 1691 he was appointed Chief Justice of the Irish Common Pleas, at the personal request of William III. This was a notable mark of royal favour, as the office had already been promised to John Osborne, the Prime Serjeant, and the decision to prefer Pyne may reflect Osborne's growing unpopularity with his political superiors.
He was promoted to the office of Lord Chief Justice of the King's Bench for Ireland in 1695. He held the latter office until his death, although he seems to have been in failing health in his last years, and frequently visited Bath in hope of a cure. As Chief Justice he clashed with the powerful cleric William King, Bishop of Derry and future Archbishop of Dublin, who accused him of interfering in Church affairs. He is listed as one of the trustees of the King's Inns in 1706.
Pyne was a substantial landowner in County Cork: he lived mainly at Waterpark, near Carrigaline. In 1703 he bought Blarney Castle, but sold it a few months later, apparently on the basis of a rumour (unfounded as it turned out) that the dispossessed owners, the MacCarthys, were about to recover it. He also owned an estate at Ashley in Surrey, where he died. He is chiefly remembered nowadays as the builder of Ballyvolane House near Fermoy, although it was not completed until a considerable time after his death.
He married Lucy Montagu, daughter of the Duke of Montagu. His only son Henry married Anne Edgecume, daughter of Sir Richard Edgecumbe and Lady Anne Montagu, and sister of Richard Edgcumbe, 1st Baron Edgcumbe. Their daughter Anne married Sir Henry Cavendish and was the mother of the statesman Sir Henry Cavendish, 2nd Baronet, whose descendants took the title Baron Waterpark.
He also left substantial lands, including Ballyvolane itself, to his nephew Robert Wakeham, the son of his sister Jane. As a condition of inheriting laid down in his uncle's will, Robert adopted the surname Pyne; the Wykeham Pynes remained at Ballyvolane for several generations.
In 1698 the Irish born author and publisher John Dunton who was on a visit to Dublin, gave a favourable picture of most of the Irish judiciary, including Pyne, describing them as : "men whose reputation is such that no one complains of them".
- Hart, A. R. History of the King's Serjeant-at-law in Ireland Four Courts Press Dublin 2000
- Osborough, W. N. Mysteries and Solutions in Irish Legal History Four Courts Press 2001
- Kenny, Colum King's Inns and the Kingdom of Dublin Irish Academic Press 1992
- Debretts Peerage
- Burke's Complete Peerage
- Ball, F. Elrington The Judges in Ireland 1221-1921 John Murray London 1926
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Sir John Hely
Sir Richard Reynell
| Lord Chief Justice of Ireland