William Johnson

William Johnson (1760–1845) was an Irish politician, law officer and judge of the early nineteenth century. He sat in the Irish House of Commons, served as Serjeant-at-law (Ireland) and was a justice of the Court of Common Pleas (Ireland).

He was born in Dublin, probably at Fishamble Street, the fifth son of Thomas Johnson, an apothecary who in later life qualified as a physician. The two brothers married sisters, Susan and Margaret Evans, daughters of John Evans of Dublin, and both had issue. He became Third Serjeant in 1813, Second Serjeant in 1814 and First Serjeant in 1816.