After a Wall Street Journal investigation revealed that mainland Chinese police had conducted “full…surveillance” on the Journal’s reporters working in Hong Kong, the territory’s Secretary for Security John Lee responded with a reassurance: “I can tell you for sure that only Hong Kong authorities have the power to enforce the law in Hong Kong.”

But, given the recent record of mainland meddling and Hong Kong government inaction, residents here are unlikely to take much comfort from Lee’s words.

Under Hong Kong’s functional constitution, the Basic Law, the government is supposed to enjoy a “high degree of autonomy” and has the power to oversee all matters except for foreign affairs and defense. It also guarantees residents a range of rights, including press freedom. Absent from the Basic Law is any provision for mainland police to operate in Hong Kong, raising questions about the legality of the surveillance of Journal staff.

None of this is new. And despite an increasing pattern of thuggish and possibly unlawful mainland security operations in Hong Kong, authorities here have done little in response.

After Lee Po, a British bookseller of the Causeway Bay bookstore, was abducted from Hong Kong to the mainland in 2016, Hong Kong’s then top leader said he was “highly concerned” and pledged to investigate. A similar promise was made after Xiao Jianhua, a Chinese Canadian tycoon, was abducted from a luxury hotel in Hong Kong’s financial district in 2017 and transferred to the mainland.

Nothing has come of the investigations into these incidents, which shook many Hong Kong people’s confidence in the city’s promised freedoms. Hong Kong’s chief executive, Carrie Lam, has not responded to Human Rights Watch’s letters raising these two cases.

Meanwhile, pro-democracy politicians and rights activists in Hong Kong continue to report being followed by mainland security agents, particularly during President Xi Jinping's visit to Hong Kong in July 2017.

The fact that these prominent cases remain unresolved sends a chill to all who work on “sensitive” issues in Hong Kong – investigating murky Chinese government-related financial deals, promoting human rights, or examining other issues authorities arbitrarily decide should be silenced – and could embolden action by Beijing.

If Lee really wants to reassure the public, he should announce a robust investigation into this case and regularly update the public on its progress. Otherwise, Hong Kong people are further left to wonder who is really policing them.