Overview: This collection is made up of nine volumes entitled U.S. Securities and Exchange Commission: Briefs in cases involving statutes administered by the Securities and Exchange Commission.

Overview: This collection includes materials relating chiefly to MacLachlan's activities as teacher, writer, and expert in bankruptcy law. The bulk of the collection (1932-1959) relates to his role as member of the National Bankruptcy Conference. It includes material relating to Harvard Law School matters, JAM's pre-World War II intervention activities, efforts for the Atlantic Union (1949-1959), cases in which he served as counsel, and personal affairs.