He defended the manager of Battersea Fun Fair in 1973, when the manager was accused of manslaughter after the big dipper ride malfunctioned in May 1972, resulting in the deaths of five children. This case brought him to the attention of the London solicitor David Napley, who instructed him to represent Jeremy Thorpe, the former Leader of the Liberal Party. In 1979, after successfully defending Thorpe, who was charged with three other men with conspiracy to murder Norman Scott in a case which became the cause célèbre of the decade, he became involved in several significant criminal trials during the 1980s. He practised exclusively from London chambers after June 1980.