Alexander Johnston (b. 1775) was a colonial official and judge in Ceylon [Sri Lanka]. He trained at Gottingen, Hanover, and Lincoln’s Inn, and was called to the bar in June 1800. After a period on the home circuit, he was appointed Advocate-General of Ceylon and in 1805 became Chief Justice of Ceylon. He advised the British government on the charter issued to the East India Company in 1813 and led a programme of reform in Ceylon, including establishing trial by jury and preparing a code of law. He also held the positions of president of the council of Ceylon, vice-president of the Royal Asiatic Society and privy councillor. On Johnston’s advice, the privy council became the court of ultimate appeal in colonial litigation. Johnston died in London in 1849.