Background
He was the third son of John R. Hosack of Glenaher, Dumfriesshire.
He was the third son of John R. Hosack of Glenaher, Dumfriesshire.
He became a student of the Middle Temple in 1838, was called to the bar in 1841, and practised on the northern circuit and at the Liverpool sessions. In 1875, though not a Queen's Counsel, Hosack was made a bencher of his inn, and in 1877 he became police magistrate at Clerkenwell. He died at his house in Finborough Road, West Brompton, on 3 November 1887, and was buried at Lytham in Lancashire.