Hong Kong takes pride in being one of Asia's freest cities, where basic rights and freedoms are respected, even though this may not be the case elsewhere in China.
Last month, for example, the acting tourism commissioner highlighted freedom of expression as one of the elements that provide a favourable setting for creative and technology industries; the secretary for security reiterated the government's respect for the public's right to express their views; and the chief secretary, while addressing the Pulitzer Prize Winners Workshop at Baptist University, pledged to 'protect the core value of freedom of expression'.
All these high-minded sentiments, however, had been put in doubt by the arrest of one demonstrator, 22-year-old Ip Ho-yee, who, while celebrating the award of the Nobel Peace Prize to mainland dissident Liu Xiaobo, splashed some champagne on a security guard outside the central government's liaison office.
Fortunately, the Department of Justice has decided not to press charges. But it is difficult to understand why she was arrested in the first place, unless it was an attempt to please officials who work in the liaison office.
Demonstrators are increasingly protesting outside the liaison office. Perhaps because Chinese officials are unaccustomed to public protests, the police seem to feel they have to be more protective. There seems to be a tendency to crack down on people who stage protests there.
Earlier this year, for example, the student activist Christina Chan Hau-man was arrested on a charge of assaulting a policewoman during a New Year's Day protest outside the liaison office. Chan was found not guilty at her trial, with the magistrate accepting the explanation that the policewoman was struck unintentionally as Chan was chanting slogans and gesturing with her arm.
But there seems to be a trend. The Hong Kong Human Rights Monitor has carried out a study which, it said, shows a rise in police prosecution of protesters under the Offences Against the Person Ordinance since 2007.
Of course, freedom of expression is not an unlimited right. For example, flag desecration is a criminal offence. But the Basic Law guarantees the freedom of speech and other protections, and some sceptics fear that the space for freedom of expression will gradually narrow.
In addition to arrests of demonstrators, other events have heightened such concern. These include the seizure by police of a Tiananmen Square massacre relief sculpture and two Goddess of Democracy statues on the grounds of breach of the Places of Public Entertainment Ordinance.
Still, Hong Kong is much better off than the mainland where, a few weeks ago, 23 senior Communist Party members called for an end to restrictions on freedom of expression in an open letter to the National People's Congress.
They pointed out that although under the Chinese constitution, the people are the masters of the country, in reality Chinese citizens still enjoy less freedom of speech and of the press than were entrusted to Hong Kong's people when they were 'residents of a colony'.
Hong Kong is no longer a colony but its people must continue to remain vigilant and ensure that their rights, especially freedom of speech and of the press, remain intact.
Providing security for central government officials is the responsibility of the Hong Kong authorities. While discharging this responsibility may be difficult, Hong Kong officials must not seek the easy way out by using different legal pretexts to infringe the rights and freedoms of the people here.
Frank Ching is a Hong Kong-based writer and commentator.