The "one country, two systems" concept remains unique and respected, despite recent debate on the essence of what is seen by many to set it apart - the balance of powers in our system of governance and the independence of our courts. It is in the top court that one feature of this uniqueness is to be found - the presence on the bench of an eminent overseas judge selected from a panel. From time to time, mainland academics question this arrangement. Three years ago one said only Chinese nationals should preside over the Court of Final Appeal, to reflect the principle of Hong Kong people ruling Hong Kong. More recently another said all judges of the court should be nationals with right of abode in Hong Kong. Yet another said the arrangement should end after "one country, two systems" expires in 2047. Both Chief Justice Geoffrey Ma Tao-li and his predecessor Andrew Li Kwok-nang have sprung to the defence of judicial independence. Li, as the foundation chief justice, has also defended the innovation of having an overseas judge. Calls for the removal of foreign judges mark a change in the sentiment that prevailed more than 20 years ago in negotiations between Britain and China on arrangements for the top court. These discussions would have been thorough, given that Hong Kong was to preserve the common-law system that sets it apart from the rest of the nation. It was agreed that overseas judges may serve on a non-permanent basis. As a result the judiciary chooses eminent jurists from Australia, New Zealand and Britain, three jurisdictions with which Hong Kong has affinity. Such an arrangement can only enhance jurisprudence and confidence in the independence of our judiciary. Hong Kong people's trust in judicial independence and the rule of law is undiminished. Mainland academics may have understandable reservations about the involvement of overseas judges. However, it is not just symbolic of a separate system, but a difference of substance reflecting the city's status as a special administrative region under "one country two systems". At the end of the day, regardless of nationality, what is important is that all judges rule in the spirit of the law, which is the essence of the rule of law. So long as these decisions are also in accordance with the Basic Law, there should be no grounds for concern about overseas judges sitting as Hong Kong judges. After all, they swear the same judicial oath as any Hong Kong judge, including to uphold the Basic Law.