Jack has practised at Crown Office Chambers since 1999, focusing on personal injury, insurance and commercial litigation. In 2000, he received a Pegasus Scholarship and worked in the product liability department of Chadbourne & Parke, LLP, New York, specializing in tobacco and pharmaceutical cases. Formerly, he has worked in Richards Butler's Hong Kong office (aviation & banking departments) and White & Case, London (corporate department), as well as in the Community Law Centre, Durban, South Africa. He has also worked for the UK Atomic Energy Authority (Technical Services Division). He enjoys cases raising difficult points of law, and those with a scientific or technical aspect.

Jack is a co-author of Emden's Construction Law and Butterworths Personal Injury Litigation Service.