Sir John Holker was a lawyer, QC, and Attorney General.
Holker was called to the bar in 1854 and went on to practise on the northern circuit. He became QC in 1866 and developed a substantial and lucrative practice specialising in patent law. Sir John Holker, then Attorney General, was the counsel for John Ruskin in the Whistler v Ruskin trial in 1878.
In 1880 he was elected Conservative MP for Preston and appointed Solicitor-General by Disraeli soon afterwards.
Whistler, James McNeill, Whistler v. Ruskin: Art and Art Critics, London, 1878 ; Whistler, James McNeill, The Gentle Art of Making Enemies, London, 1890 ; Dictionary of National Biography, online edition; 1st edition, vol. 27, 1891, online. Merrill, Linda, A Pot of Paint: Aesthetics on Trial in 'Whistler v. Ruskin', Washington and London, 1992 .