The rule of law has always been the greatest asset of the Hong Kong Special Administrative Region. Its legal system is rooted in the English common law tradition, with a Judiciary that dispenses justice without fear or favor. Whereas trials are fairly conducted and litigants enjoy a level playing field, basic legal principles are respected in the adjudication of cases.
On July 1, Hong Kong will celebrate its 29th year as a special administrative region of the People’s Republic of China under the Basic Law’s “50-years unchanged” formula. Since 1997, when British rule ended, Hong Kong’s development has been underpinned by its Basic Law, the constitutional instrument that embodies late paramount leader Deng Xiaoping’s “one country, two systems” governing policy. This policy, which provides that the capitalist system and way of life shall remain unchanged for 50 years, provided the city with a strong start in life in 1997, not least in respect of its legal arrangements. It has enabled Hong Kong to retain its common law system, with an independent Judiciary, independent prosecution service, and independent legal profession.
Within this context, the public interest in the HKSAR has progressively evolved since the reunification. As elsewhere, public-interest law focuses on advancing justice and the public good. It may involve the rights and interests of people or groups who feel marginalized, and is a means of achieving social justice. An obvious means of enforcing the public interest is through judicial review, in which a court determines whether a decision of public authorities or a piece of legislation is lawful and valid.
In 2016, the then-chief justice, Geoffrey Ma Tao-li, said, “Although there may sometimes be inconveniences, judicial review overall serves the public interest and facilitates the well-being of society”. Judicial review is multifaceted, and has been used to challenge restrictions on minority rights, decisions to bring criminal prosecutions, and orders that foreigners should be deported to places where they may face inhumane conditions. The Legal Aid Department, a public body, funds meritorious judicial reviews.
The public interest requires that justice is administered properly, and the three arms of the HKSAR’s governance system — the executive, the legislature and the Judiciary — have a shared responsibility for sustaining the rule of law. In the criminal justice area, the public interest means that nobody should be prosecuted by the Department of Justice unless there is a reasonable prospect of conviction, and a mere suspicion does not suffice.
The Department of Justice adheres to the public-interest criteria developed in the common law world, and may decide, evidence notwithstanding, that a prosecution is unnecessary. It may, for example, decide not to prosecute an individual if the offense is stale, technical or otherwise undeserving of criminal proceedings. If, moreover, a suspect is young or old, or the victim opposes a prosecution, or the sentence after trial is likely to be trivial, or the suspect wants to assist the authorities, an alternative to prosecution may be in the public interest, such as a formal caution, particularly if an individual is of good character.
The factors that may properly be taken into account in deciding where the public interest lies will vary from case to case. Generally, the more serious the offense, the more likely the public interest requires prosecution to be pursued. However, the resources available for prosecution are not unlimited, and should not be used in inappropriate cases.
If a private citizen is aggrieved by the Department of Justice’s decision not to prosecute a suspect, there is a right of private prosecution. However, it is not untrammeled, and the department has an overarching responsibility to ensure the right is not abused. For example, if the evidence does not suffice, it would not be in the public interest for a suspect to be privately prosecuted, with the trauma and expense this may entail. If a private prosecution is frivolous, malevolent or otherwise flawed, it is in the public interest that it be terminated, as prosecution must never become a tool of persecution. In those circumstances, the Department of Justice should terminate the prosecution.
An important aspect of the public interest in the criminal context involves the public-interest defense. When, for example, the Hong Kong Safeguarding National Security Ordinance was enacted in 2024, it contained a limited public-interest defense (ss.30, 35). If a person is charged with the unlawful disclosure of State secrets, it is a defense that the disclosure was made to reveal the circumstances in which the government’s performance of its functions according to law was seriously affected, or to reveal a serious threat to public order, public safety or public health. However, the disclosure should only be to the extent that is strictly necessary to expose the situation. Moreover, the public interest in making the disclosure should manifestly outweigh the public interest in not making the disclosure.
Whereas the public interest looks to the future, asking what outcome best serves the community, the interests of justice address deontological questions, including whether the process was fair and if rights were respected. In other words, the interests of justice provide an overarching standard against which the entire system can be judged, and they subsume and also exceed the public interest
This public-interest defense has been widely welcomed, including by Hong Kong’s legal community. It can, for example, be invoked if a disclosure was made in an emergency, including protecting the public from an imminent threat. It is useful to whistleblowers, journalists and activists who make disclosures without intending to endanger national security. Whereas the threshold for invoking it is high, the public-interest defense is a means of achieving a balance between ensuring security on the one hand with transparency and accountability on the other. After all, if a disclosure is made for the public good, there may be no public interest in criminalizing it.
Throughout the common law world, the public interest requires authorities to protect the integrity of the criminal justice system, whether physically or by other means. This, for example, may require limitations on jury trials, with cases being tried by single judges or panels of judges. In the United Kingdom, the Criminal Justice Act (2003) allows a trial to be conducted by a judge alone if it is decided there is a “real and present danger” of jury tampering, and that, once steps are taken to neutralize the threat, the likelihood of it arising would be “so substantial as to make it necessary in the interests of justice for the trial to be conducted without a jury”.
In 2015, when the Judicial Committee of the UK’s Privy Council considered an appeal from the Turks and Caicos Islands, Lord Hughes said “An order for trial by judge alone can be made where the interests of justice require it, just as in England it can only be made where it is necessary.” (Misick & Ors v R [2025] UKPC 31)
In Hong Kong, a three-judge trial is possible instead of a jury trial in national security cases where the interests of justice (which include the public interest) require. If the secretary for justice issues a certificate directing that the accused be tried without a jury on the “grounds of, among others, the protection of State secrets, involvement of foreign factors in the case, and the protection of personal safety of jurors and their family members,” the Hong Kong National Security Law provides that the case will be tried in “the Court of First Instance without a jury by a panel of three judges” (Art 46). If an accused person is aggrieved by the decision, he can challenge it by judicial review, although he will need to show it was taken in bad faith.
This mirrors the situation in the Republic of Ireland, where a three-judge panel (“Special Criminal Court”) can replace juries where the public interest so requires, as where national security is endangered, or where witness intimidation is feared, or where serious and organized crime is involved.
Although the public interest and the interests of justice overlap, they are not necessarily the same. The interests of justice is a wider concept, encompassing systemic integrity, individual rights, fairness between the parties and the legitimacy of the overall process. The public interest is a component within that wider framework, but not all-embracing. Whereas the public interest looks to the future, asking what outcome best serves the community, the interests of justice address deontological questions, including whether the process was fair and if rights were respected. In other words, the interests of justice provide an overarching standard against which the entire system can be judged, and they subsume and also exceed the public interest.
Since 1997, the “one country, two systems” policy has worked well in Hong Kong, and its “50 years unchanged” formula has sustained its legal system. Everybody expects it to continue after 2047, meaning its common law paradigm, including the public interest, is secure. This is reassuring not only for residents but also for everybody who values the rule of law.
The author is a senior counsel and law professor who was previously the director of public prosecutions of the Hong Kong Special Administrative Region.
The views do not necessarily reflect those of China Daily.