In June 1788 John Scott became Solicitor General, one of the principal lawyers employed by the Crown and commonly known as the government's junior law officer. He remained in post for almost five years, before advancing to the senior office of Attorney General, where he remained for a further six. During that eleven-year period, Scott worked first with Archibald Macdonald, and later with John Mitford. Scott's years as a law officer were onerous ones for him. He had considerable responsibilities in three important areas: parliamentary debate, civil and criminal prosecution, and executive consultation and administration. Not only was the actual volume of work large, but the nature of the work placed pressures upon him as a result of the peculiar characteristics of the posts.

The offices of Attorney and Solicitor General had a long history. At least since the reign of Henry III, English monarchs followed the growing practice of appointing one or more legal representatives, first for particular tasks and then in anticipation of whatever matters might arise to which the monarch could not personally attend. Persons who acted for the Crown in a legal capacity were described as King's Attorneys. ‘Attorney’ not yet having come to designate a separate professional class, it merely described a legal representative. The earliest use of the title ‘attorney general’ actually referred to individuals appointed by the Duke of Norfolk in 1398. Gradually the practice evolved of appointing two King's Attorneys, and from 1472 the post was held singly.