After practicing law for four years, he was appointed Chief Justice of
Nova Scotia in 1790, likely helped by his mother's friendship with Lord Mansfield, a cabinet minister. His successor said that "in cases involving runaway slaves Strange required the fullest proof of the master's claim" and that since this was difficult to produce "it was found generally very easy to succeed in favour of the Negro". Blowers, as attorney general, and Strange frequently discussed how to proceed in such matters, and Strange decided to move slowly rather than "throw so much property as it is called into the air at once". Strange supported the development of Kings College from his position on the board of governors. He donated his law library to the lawyers in Nova Scotia, which laid the foundation for the present library of the
Nova Scotia Barristers' Society. He also was president of the
North British Society.
Benjamin West painted Strange's full-length portrait, which hangs in the Nova Scotia court. ==Assigned to British India==