Murray had repeatedly refused to become a Member of Parliament, saying he had no interest in politics. In 1742, however, the government of Sir Robert Walpole fell, and Murray's brother-in-law, the Earl of Nottingham, became First Lord of the Admiralty in the new Cabinet. With this added political influence, Murray hoped to be appointed to a government office, and when Sir John Strange resigned as Solicitor General, Murray was made a Member of Parliament for Boroughbridge on 15 December 1742 and immediately succeeded Strange as Solicitor General.