Jennings, who was attorney-general for several circuits in Wales, had a grant of a house in Lincoln’s Inn Fields in 1686, which had been forfeited by Sir Robert Peyton†, and also of lands in Wrexham and Holt in Denbighshire. Jennings remained an active lawyer after the Revolution, taking many cases before the House of Lords, and in 1695–6 he and Sir Thomas Powys* opposed grants of land in Wales to William III’s Dutch favourites, the earls of Portland and Rochford. He had a personal interest in these matters since his own salary, and those of the Welsh judges, came out of the revenue of the principality. He also assisted Powys as counsel for Sir John Fenwick†, the Jacobite conspirator. On the accession of Queen Anne, he was allowed to take silk.5 CJ, xiii. 438; xviii. 339; HMC Lords, n.s. i. 29, vi. 311; Cal. Treas. Bks. x. 1014, 1408, 1413, 1445; xxix. 325.
Returned for East Looe in 1713 on the Trelawny interest at the recommendation of Lord Treasurer Oxford (Robert Harley*), Jennings was classed as a Tory in the Worsley list. Between April and June 1714 he managed a bill to prevent cattle theft, and reported and carried up a bill to settle the revenues of several Welsh dioceses and to annex various prebends to Oxford and Cambridge colleges. Jennings’ advanced age no doubt explains his retirement from Parliament in 1715. A member of the SPCK, he continued to take an active interest in Church affairs and played an important role in the purge of Jacobite charity school teachers in October 1716. He died on 12 June 1725, and was buried in the Inner Temple. His son, Philip, sat for Queenborough 1715–22.6 Info. from Dr Rose; Williams, 81.