Oakes received a Bachelor of Arts from the University of Cambridge, which is a collegiate university in England with origins in the early thirteenth century. Its collegiate structure combines central university examinations and teaching with semi-autonomous colleges that admit and house students.
He was admitted to the bar in England in 1978. Admission to the English bar marked his entry into the legal profession in England, the country in which he later practiced in London.
Oakes worked as a partner of Rowe & Maw, a London law firm founded in 1895 that was known for its corporate, construction, pension, insurance, property, and employment practices. The firm built its reputation in the City of London and, by the early 2000s, had offices in Manchester and Brussels as well as London.
On February 1, 2002, Rowe & Maw merged with the Chicago firm Mayer, Brown & Platt to form Mayer, Brown, Rowe & Maw, a transatlantic partnership that later shortened its name to Mayer Brown. Oakes's partnership belonged to the London practice of the firm during this period of expansion in the English legal market.
