Warren was one of six brothers, all educated at Westminster school, whose success in their chosen professions was promoted by their parents’ court connexions. On 19 Jan. 1790 he joined the Whig Club and was subsequently a Friend of the People. He practised as a barrister, took silk and in May 1819 became attorney-general to the Prince of Wales, for whom he had acted, and, shortly afterwards, chief justice of Chester, the last to hold the office, since after his death no successor was appointed.3Old Westministers, ii. 966; W. R. Williams, Gt. Sessions in Wales, 54.
At the same time Warren entered Parliament on a vacancy at Dorchester, on Lord Shaftesbury’s interest, a seat in which he succeeded his fellow lawyer Sir Samuel Shepherd. Tierney, who had got wind of Warren’s intended promotion in December 1818, predicted that he would be ‘a formidable opponent, and, like all new converts, inveterate against his old friends’. In his first session, Warren came to the assistance of administration in the debate on the address, 24 Nov. 1819, stating in reply to Lord Nugent the grounds for asserting that the riotous Manchester meeting of 16 Aug. was illegal. Charles Williams Wynn reported next day that he ‘spoke but indifferently ... and appeared much mortified and annoyed by Burdett’s attacks’.4Grey mss, Tierney to Grey, 21 Dec. 1818; NLW, Coedymaen mss 12, f. 930. Warren died 12 Aug. 1829.