Authorities proposed expanding the scope of offences related to seditious intention to also cover, among other things, bringing a Chinese citizen, local resident or a person in Hong Kong into hatred or contempt against the central and local authorities, as well as inciting anyone to commit unlawful acts.

They also suggested improving existing offences to curb acts of espionage and collusion with external elements “with the intent to endanger national security”, with the condition also used to determine treason and insurrection offences.

But the paper stopped short of spelling out what constituted intent that would endanger national security.

“I am worried that these new, or in some cases expanded, provisions are vague and overbroad, and could be used to target peaceful political activity,” said Thomas Kellogg, executive director of the Asia Law Centre at Georgetown University in the United States.

Such an approach would be in line with the government’s use of the Beijing-imposed national security law to target its critics, including opposition legislators, journalists and NGO activists in recent years, Kellogg said.

He added that the requirement of “intent” under some of the crimes such as treason and insurrection was vague.

“I’m worried that the proposed Article 23 legislation, with its vague references to ‘intent’, could be misused in a similar way,” he said.

Chong Ja Ian, an associate professor of political science at the National University of Singapore, said concepts such as “intention” and “disaffection” in the consultation paper were difficult to define.

“Such sentiments are not directly observable, since they rest inside people’s minds. I suppose a lot will come down to standards of evidence,” he said.

“I suppose it is possible to draw some conclusion about intention from observable behaviour but standards of evidence remain. For instance, it is not necessarily self-evident whether the collection of fertiliser is intended for the purposes of selling, using or to produce explosives.”

He added that the history of concepts such as “seditious intention” in jurisdictions like Hong Kong was rooted in colonial rule, while the recent consultation linked local security issues to the Chinese Constitution and laws, which provided prosecutors and judges significant leeway in interpreting the meaning of “intent” – particularly in relation to national security issues.

Ryan Mitchell, an associate professor of law at Chinese University, said there were ambiguous aspects to assessing seditious intention, adding that he wondered whether further efforts could be made to bring clarity.

But former security chief Lai Tung-kwok, now a lawmaker, said the phrase itself already provided enough clarity, arguing that the use of the word “intent” had been backed up by countless legal precedents and the burden of proof was high.

“[Authorities] must use a lot of concrete evidence to prove your intention,” he said.

Ronny Tong Ka-wah, a senior counsel who sits on the government’s key decision-making Executive Council, said Hong Kong courts were “very experienced” in determining intention in offences and the handling methods were similar in both national security and ordinary criminal crimes.

Citing theft of state secrets as an example, Tong said an individual would not be considered to have any intention of endangering national security provided he or she had no reasonable grounds to believe information contained a state secret.

Basic Law Committee member and lawmaker Priscilla Leung Mei-fun said she would wait until the final Article 23 bill was released before determining whether it was necessary to ask authorities to elaborate on “intent to endanger national security” or to leave the matter to the courts, but echoed the threshold to prove it was “already very high”.

Hong Kong courts, while handling a number of rioting cases over the past few years related to the 2019 anti-government protests, have found that the possession of protest items in a defendant’s house constitutes sufficient evidence to prove criminal intent.