An incitement offence targeting hatred against the Hong Kong government may be included in a long-shelved security bill, a top city official has revealed days after online users mocked a police officer who died while on duty.

Secretary for Security Chris Tang Ping-keung raised the possibility of a new clause under Article 23, while being grilled by lawmakers on Wednesday, with the Fire Services Department separately launching an investigation into complaints against staff accused of ridiculing the dead senior police inspector.

Officer Lam Yuen-yee died during an anti-smuggling sea operation on Saturday, sparking a declaration from the police chief that the force would spare no effort in bringing the “cold-blooded” criminals to justice. Lam’s vessel was rammed by a speedboat and capsized in a chase.

A top Beijing official overseeing Hong Kong affairs was among government figures offering their condolences on Wednesday.

Article 23 of the Basic Law, the city’s mini-constitution, states that the city has a responsibility to enact legislation to safeguard national security.

Despite Beijing last year imposing the national security law on Hong Kong to target secession, subversion, terrorism and collusion with foreign forces, central authorities still expect the local administration to fulfil its constitutional duty. The Article 23 bill was shelved in 2003 after 500,000 people took to the streets in protest.

On Wednesday, in a question to Tang, also a former police commissioner, one lawmaker asked how he intended to deal with hatred directed at his ex-colleagues and the government, citing a wave of recent online gloating triggered by Lam’s death as an example.

Tang noted that the Beijing-decreed security law stopped short of targeting the actions raised by the legislators, and the legal power to punish such behaviour came only through the Crimes Ordinance.

Under that ordinance, those who utter seditious words or publish content with an intention to bring hatred and contempt of the government face a maximum penalty of two years in jail and a fine of HK$5,000 (US$640) on first conviction.

“We will look at whether there is a need to incorporate those offences from the Crimes Ordinance into Article 23. This will be the direction we will proactively explore,” Tang said.

He added that he hoped the bill would be ready by the next legislative term.

Secretary for Security Chris Tang.

Former director of public prosecutions Grenville Cross shrugged off suggestions the move might dampen the city’s freedom of speech, saying the offence was already covered under the current law.

He said he believed that any proposed changes would only help clarify ambiguities. “If the present offence provision is a legitimate curb on free speech, then any replacement provision which clarifies things will likewise be legitimate,” he said.

But human rights law scholar Michael Davis, a resident fellow at the Woodrow Wilson International Centre in Washington, disagreed, fearing it would amount to a speech crime.

The academic, who previously taught at the University of Hong Kong, said the city as an open society should observe international human rights. He added that Tang’s suggestion “would require that the speaker encourages imminent violence, and not merely opposition or hatred against the government”.

“Anything less will have a dramatic chilling effect on free speech, as the speaker will not know when he or she has crossed the line,” Davis said.

Wednesday’s question on the inspector’s death was filed by Steven Ho Chun-yin from the Democratic Alliance for the Betterment and Progress of Hong Kong.

Ho expressed fear that incitement of hatred towards authorities would go underground, scattering across online forums, even as police had been targeting opposition groups, a move critics have argued was aimed at stifling political dissent.

Grenville Cross, former director of public prosecutions.

Tang on Wednesday touted the success of law enforcement agencies.

Ho then turned to Lam’s death. “They made a song titled Don’t Look For Something Fallen Into the Sea to incite hatred against police and conflicts against our government,” he said, referring to a parody of a hit rap song on YouTube.

Meanwhile, in response to complaints over alleged online remarks made by its officers over Lam’s death, a fire services spokesman said the department attached great importance to personnel conduct and discipline.

The spokesman declined to say how many firefighters were involved or if they were suspended from duty.

The Disciplined Services Consultative Council and Government Disciplined Services General Union, two umbrella groups representing many unions from the sector, condemned speech that “rubbed salt on the wound”.

“These speeches were not only disrespectful to the late senior inspector, her family and police officers injured in the incident, they undermined the spirit of officers charged with upholding law and order,” the council said in a statement.

Police commissioner Raymond Siu Chak-yee also relayed “deepest condolences” from the Hong Kong and Macau Affairs Office (HKMAO), the cabinet-level body overseeing local matters, to Lam’s family on Wednesday.

A spokesman for the office, citing HKMAO chief Xia Baolong, praised the late officer “for her dedicated service to the police force for more than a decade, and her professionalism in putting the spirit of safeguarding national and Hong Kong security into practical action”.