Lewis specialises in commercial and cross-border litigation. His significant cases in recent years include: Secilpar v Fiduciary (2004) where the Gibraltar Court of Appeal set out the principles to be applied when seeking Norwich Pharmacal disclosure in aid of foreign proceedings; TGWU v Secretary of State for Defence (2005), where the Supreme Court of Gibraltar clarified the modern legal basis for asserting jurisdiction over the UK Government in Gibraltar; Bols v Superior Yacht Services (2006), where the Privy Council confirmed the test applicable to whether an agreement on jurisdiction exists within the meaning of the EU Judgments Regulation.
Lewis has also built up a strong maritime and public law practice. His client base is mostly international and he works regularly with major London and international law firms. As one of Gibraltar's most experienced litigators, he has frequently appeared before the Gibraltar Supreme Court and Court of Appeal over the past 20 years.
He is also one of the few Gibraltar lawyers with experience in cases before the Privy Council and the European Court of Human Rights. Lewis is recommended as a top litigator in Chambers Global 2008-2009, the Legal 500 2008 and by European Legal Experts 2008. Lewis has also sat as Chairman of a number of tribunals, statutory boards and boards of inquiry over the years. He studied law at King's College, London and the Inns of Court School of Law and Joined Hassans on being called to the Bar in 1986. He became a Partner in 1993.