In a high-profile national security trial in Hong Kong, former vice-chair of a now-dissolved pro-democracy group Albert Ho Chun-yan pleaded guilty to inciting subversion, while prosecutors invoked a legal principle to implicate his co-defendants in efforts to undermine China's ruling system.

The trial of the disbanded Hong Kong Alliance in Support of Patriotic Democratic Movements of China and its former leaders began in late January, focusing on charges of inciting others to subvert state power under the city's national security law.

The case involves actions from mid-2020 to late 2021, where the group allegedly promoted ideas aimed at ending the Communist Party's leadership, seen as a direct challenge to China's constitutional framework.

Ho, a veteran activist and lawyer, admitted guilt on the opening day, acknowledging continued advocacy for the group's goals even after the security law took effect. Prosecutors highlighted how these efforts, through various channels like events and publications, sought to stir public discontent against the central government.

The other two defendants, Lee Cheuk-yan and Tonyee Chow Hang-tung, denied the charges. Prosecutors applied a co-conspirator's rule, using the guilty plea and related actions to argue that all involved knowingly participated in a shared plan to disrupt the political order.

Court proceedings included rejected attempts by Chow to introduce expert testimony from a Taiwanese academic, deemed irrelevant.

Similar bids to change judges, dismiss charges, or allow remote witnesses from abroad were also dismissed for lack of merit.

Observers noted these tactics resembled delays in other security cases, suggesting an intent to prolong proceedings or make political statements.

The alliance had long pushed for democratic reforms, including calls to end one-party rule, which authorities view as subversive.

This principle of shared liability has proven effective in prior cases, such as one involving plans to paralyze the government through legislative tactics, leading to convictions.

The trial, handled by designated security judges Alex Lee Wan-tang, Johnny Chan Jong-herng, and Anna Lai Yuen-kee, is set to last several months.