The scandal over fake vaccine exemption certificates raised serious concerns about public health. Officials moved to invalidate more than 20,000 of the suspect documents issued by seven doctors. Now they must think again. Last week, a court ruled there was no legal power permitting the government to render the certificates invalid. The ruling is significant on several levels. Chief Executive John Lee Ka-chiu responded by pledging his administration would abide by the law and respect the judgment. Legal advice on the best way forward is being provided. Appealing against the ruling might not be the best strategy. The arguments the government presented were not convincing. Mr Justice Russell Coleman said there had been an attempt to “play with words” and to “rewrite the historical narrative”. The judge found there was no lawful mechanism for officials to invalidate the certificates. Coleman said the government appeared to have failed to consider the legal implications before announcing the move. As he said, a minister’s legal powers come from legislation, not a press release. Officials were acting in the interests of public health. Holders of the fake certificates can use them to effectively circumvent the vaccine pass scheme, but no matter how desirable the policy, it must comply with the law. The government accepted some of the certificates might be genuine. Around 16,000 of them will expire by the end of next month anyway. Rather than appealing against the judgment, officials could amend the regulations. This can be done quickly and would provide a clear legal basis for invalidating the certificates. It would be a legitimate response and one that would safeguard public health. The change to regulations should ensure fair treatment for patients entitled to an exemption. It should also make clear who has the power to invalidate the documents and on what basis. Hong Kong government has no power to invalidate Covid jab exemptions: court While the case might cause inconvenience to the government, it demonstrates Hong Kong’s rule of law is working. The courts have a responsibility to ensure government policies fall within the powers it enjoys. The process of judicial review is part of the checks and balances that ensure good governance. The case was brought by a serial litigant who appeared to lack a direct personal interest in the case, but the judge allowed the challenge to proceed because to do so was in the public interest. He said the legal action involved “vindicating the rule of law”. This spirited judgment demonstrates the independence of Hong Kong’s judiciary, which has been called into question by critics amid the city’s political changes and divisions. Fighting Covid-19 often involves imposing measures that restrict the way in which people can live their lives. This case is a reminder that those policies must be based on a sound legal footing.