Hay’s grandfather James Hay, the son of John Hay of Haystoun, near Peebles and his first wife Grisel Thompson, was a physician in Edinburgh. His younger brother Adam Hay served in the army, 1747-68, and was Member for Peeblesshire, 1767-8 and 1775, when he died deep in debt. Dr. James Hay, who had succeeded his father in 1762, bought Adam’s estate of Soonhope and acquired other Peeblesshire property. In 1804 he claimed the baronetcy of Hay of Smithfield, dormant since the death of his grandfather’s degenerate third cousin, Sir James Hay, 3rd baronet, in about 1683; and on 9 Nov. 1805 he established before a jury in Peebles that he was entitled to assume it.
His eldest surviving son John Hay was bred to the Scottish bar, but achieved no distinction there. He was in Greece in April 1819 and so out of contention for an opening for Linlithgow Burghs. He succeeded to the baronetcy and entailed estates in May 1830.
Hay’s confidence in his chances of being returned for Peeblesshire at the 1832 general election proved to be justified, and he sat for the county as a Conservative until his retirement in 1837.
