Sean was called to the British Columbia Bar in 2002. Throughout his career he has practiced in civil, administrative and constitutional litigation. His work has included lengthy civil trials, public inquiries, sensitive internal investigations, class actions and many pro bono cases engaging public interest issues. He received a (then) Queen's Counsel designation in 2019. He is an honorary lifetime member of the B.C. Freedom of Information and Privacy Association and was a recipient of the 2022 Charles Bury award from the Canadian Association of Journalists on behalf of lawyers defending press freedom and journalists’ rights.