John 承辦全系列的重大訴訟和辯護工作，包括資產追蹤、跨司法管轄區糾紛以及商業和信託訴訟。John 曾在耿西島皇家法院 (Royal Court of Guernsey) 和耿西島上訴法院 (Guernsey Court of Appeal) 的許多重大訴訟案件中擔任律師，也是耿西島少數曾在樞密院 (Privy Council) 擔任律師的律師之一。在過去 12 個月內，他曾擔任突破性信託訴訟案件的首席律師。

John was a founder member of ICC FraudNet, and is a member of the UK Fraud Advisory Panel. He was also a founder member of the Guernsey Royal Court Working Party which completely reviewed the island's Civil Procedure in 2008. He is also a member of the Association of Contentious Trust and Probate Specialists and is a Notary Public. John was the first elected Head of the Guernsey Bar in 十一月 2008 and was re-elected to the role in 2010. In 2014 John was awarded ACTAPS Offshore Contentious Lawyer of the Year Award. In 2015 he was awarded the "most highly regarded" classification for Asset Recovery by Who's Who Legal – one of only five offshore lawyers in the world to be awarded such accreditation.