Johnstone lost his seat at Dumfries in the 1790 election after a display of robust independence in Parliament.
Johnstone’s health was failing and he was thereafter probably absent from the House. He died 3 Sept. 1794. His brother William wrote to Hiley Addington (6 Sept.),
I have had the misfortune to lose my brother, Sir James Johnstone, after a long illness, which he bore without a murmur. He was most generally beloved, but not more than he deserved, for there never was a warmer heart or a more honourable mind. As a public character his views were always perfectly pure and disinterested and you will not wonder that I am sincerely afflicted by his loss.
CJ, xlviii. 318; Sidmouth mss.
