In 1765 he was touted as a possible successor to William Carmichael as Archbishop of Dublin, though the Irishman Arthur Smyth was ultimately appointed.
Garnett married Dorothea, the youngest daughter of Sir Thomas Molyneux, 1st Baronet.
[7] According to the DNB, the John Garnett who was appointed dean of Exeter in February 1810, and died 11 March 1813, in his sixty-fifth year, was the Bishop's son.
Elsewhere Burdy praised Garnett as "a pious, humble, good-natured man, a generous encourager of literature, kind to his domestics, and justly esteemed by all those who had an opportunity of knowing his virtues".
On seeing it at the Duke of Newcastle's, to whom it was dedicated, Lord Morton remarked that it was 'a very proper book for the ante-chamber of a prime minister.'