In Jan. 1809 he was appointed Dean of the Arches and judge of the Prerogative Court of Canterbury, and was admitted to the Privy Council. In 1833 he was appointed judge of the High Court of Admiralty. In the following year he was made vicar-general to the archbishop of Canterbury and resigned the offices of Dean of the Arches and judge of the Prerogative Court. As a judge he earned golden opinions ‘for inflexible impartiality and great strength and soundness of judgment.’ His judgments appear in the ‘reports’ and several were printed separately.
About 1803 he purchased the estate of Merthyr Mawr, Glam., and erected there a gracious mansion and stored in it a library of some 30,000. He took an active part in the politics of his native county, and consistently supported Sir Christopher Cole, the Tory member. He was a most active member of the volunteer movement during the Napoleonic war and attained the rank of lieutenant-colonel. He assisted actively in the establishment of King's College, London, and was a Fellow of the Royal Society and of the Society of Antiquaries.
He m. Judy, youngest daughter of Peter Birt of Wenvoe, on 8 Sept. 1787, and d. at Merthyr Mawr on 26 Aug. 1838. He left one son, John Nicholl (q.v.), and three daughters.
Henry John Randall, F.S.A., (1877-1964), Bridgend