James Lockyer obtained his LLB at the University of Nottingham in 1971 and is a member of the Bar in England. Between 1972 and 1977, he was an Assistant Professor of Law at McGill University and then the University of Windsor. In 1977 he was called to the Ontario Bar and began to practice criminal law. He has been a criminal lawyer for 36 years. Since 1992, the majority of his practice has involved unravelling wrongful convictions. He has received five honorary doctorates from four Canadian Universities and the Law Society of Upper Canada. In 2012, he received the Award for Justice (Advocates Society).

Mr. Lockyer is a founding director of the Association in Defence of the Wrongly Convicted (AIDWYC), a Canada-wide organization that advocates for the wrongly convicted. In that capacity, he has been involved in several high profile wrongful conviction cases including those of Guy Paul Morin (1995), David Milgaard (1997), Steven Truscott (2007), William Mullins-Johnson (2008) and Tammy Marquardt (2011).