Danish Siddiqui / Reuters

Five years ago, China said it would screen candidates for election to chief executive in Hong Kong. Some of the protesters who first unfurled umbrellas in response to that announcement, to complain about Beijing’s heavy finger on the electoral scales, were arrested on Friday. Joshua Wong—who, as a 14-year-old, helped organize those protests—was among those detained. China’s promise, 30 years ago, of One Country, Two Systems gave millions the assurance that their rights and wealth would be guaranteed in the new Hong Kong Special Administrative Region. The events of the past few weeks, though, pose a question: Can the system that has seen the city-state prosper survive?

The dual regime that has paid off for everyone is under greater pressure than ever before. China’s troops wait on the mainland as the Hong Kong Police Force, once considered the best in Asia, tries to keep control without outside help. But the protests aren’t stopping. Fear for the future—fear that rights, once lost, will never come back—is persuading thousands that they must take action now to defend themselves.

The people of Hong Kong need time, space, and security to work toward a political solution. And the simplest way to provide that—a solution that serves the interests of all concerned—is for Britain to right a historic wrong, and confirm eligible Hong Kongers as British citizens.

This isn’t the first time that the people of Hong Kong have feared for their future. Before the U.K. returned control of Hong Kong to China, in 1997, many worried that Hong Kongers wouldn’t trust the new regime. That’s why the British and Chinese governments agreed on the Sino-British Joint Declaration in 1984 and lodged it as a treaty with the UN. The agreement made clear what was planned, and pledged that the international accord would endure for 50 years. Five years later, the declaration would prove essential in calming Hong Kongers who learned of unrest across China and watched the violent repression in Tiananmen Square.

Many considered fleeing—but again, Britain steadied the ship. In 1981, Hong Kongers’ status changed from the same as all other British citizens—known as citizens of the U.K. and colonies—and they became citizens of British dependent territories, geographically split and without the right of residency in the U.K. The Joint Declaration agreed that Hong Kongers would become British nationals (overseas) at the handover, but as emigration began to threaten the city’s stability, Britain partially reversed the decision by giving those considered most essential to the good governance of the city full British citizenship, as an inducement to stay. By guaranteeing their rights, Britain gave them the certainty that they could leave whenever they chose and so bought time. Hong Kongers could get used to their new rulers and become confident about their future.

Now, as then, those on the street and in the government need time and faith if the political settlement necessary to end the protests is to have a chance. Once again, Britain can help. Today, returning rights that British nationals (overseas) lost almost 40 years ago would give those wondering what the future brings the confidence to wait, secure in the knowledge that they have options whatever the outcome of the current unrest. It could lower the stakes of the protests, and encourage the political dialogue that will be the only solution to the present unrest.

The decision to strip Hong Kongers of their rights as British citizens was wrong and counterproductive. Instead of defending the U.K. from mass migration, it cut Britain off from the Asian economic miracle, and removed rights from people who had grown up on the rule of law. We need to correct that mistake, and not just for ourselves.

More important, British nationals, wherever they live, should have access to the certainty of the rule of law. They should also have the freedom to make decisions about their lives at an appropriate pace, without feeling the need to preempt events. The irony is that without the knowledge they can leave, many will lose the confidence to stay, triggering an early and, if wisdom returns, unnecessary migration to the U.K.

Britain’s role doesn’t end with recognizing the rights our own nationals should have enjoyed all along. The U.K. is intrinsically tied to Hong Kong through the rule of law, and it shares reputational risk with the judges on the island.

Overseas nonpermanent judges have sat for decades on the Court of Final Appeal, Hong Kong’s supreme court. They are drawn from other common-law jurisdictions—Britain, Australia, Canada, and New Zealand—and provide the guarantee that Hong Kong justice is up to international standards and not subject to the whims of the Communist dictatorship next door.

On the mainland, justice is not equal. Like the members of the old European aristocracies, members of the Communist Party can be tried only by their peers, not by the ordinary courts. Widespread accusations of corruption and poor governance mean few have confidence the Chinese judiciary is independent. That’s bad for individual rights, but also bad for business. Hong Kong is different. The rule of law underwrites the city’s prosperity and gives confidence to traders and investors around the world. It is no exaggeration to say that Hong Kong’s judicial system has ensured the island’s prosperity. That’s why the new extradition law matters so much.

Carrie Lam, the Hong Kong Special Administrative Region’s chief executive, says the draft bill on extradition is intended to help prevent criminals from using the territory to hide. But extradition is about more than preventing crime; it is a recognition that another legal system is fair. In China, that’s just not true. China’s execution of hundreds of prisoners and its use of arbitrary detention and mass incarceration to control political activity across its empire stands in stark contrast to the actions of the still-bewigged judges in Hong Kong.

The city-state is not just an offshore Shanghai. It’s a haven of legal confidence in a region that struggles with corruption, and whose wealth is constrained by the grasp of oligarchs—including the so-called red princes in China.

China’s use of the law as a means of control, not justice, puts it in direct opposition to the principles of the common law. The extradition bill would extend the remit of that system to Hong Kong, making British judges complicit. The risk to the reputation of the British legal system, and other legal systems, is clear. This is not just about Hong Kong anymore; it’s about us.

But the implications are much wider. Many investors have seen their returns multiply as they used one of Asia’s pivotal nodes to generate Asian and global trade. Hong Kong judges created that confidence through the rule of law, acceptance of standards, and a respect for the international norms.

Now China is trying to use that same justice system to underwrite its mercantilist expansion through its Belt and Road Initiative. Declaring Hong Kong justice unjust would directly threaten Beijing’s new imperial dream. It would also weaken investors’ confidence in the region’s markets, potentially undermining the prosperity of millions. That’s why returning their rights is not just good for Hong Kongers; it’s good for everyone.

More than 20 years after the handover, Britain no longer exercises any direct sway over Hong Kong. The days of colonial rule are long past, and no one wants them back. But the ties between Britain and Hong Kong on the basis of our intertwined histories and economies remain strong, bolstered by our commitment to British nationals (overseas) and the role our judges play within the common-law system. Britain can have a role in helping Hong Kong prosper once more, by remembering that imperial pasts confer ongoing duties, and by guaranteeing the rights of those who grew up in the shadow of the Crown.

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