FILE - Pro-democracy lawmakers Au Nok-hin, in yellow helmet, and, Claudia Mo, right, argue a pro-Beijing lawmaker during a demonstration of an anti-riot vehicle equipped with water cannon by Hong Kong police at the Police Tactical Unit Headquarters in Hong Kong, Monday, Aug. 12, 2019. A Hong Kong court began mitigation hearings for prominent pro-democracy activists who were convicted under a national security law and now face up to life in prison. (AP Photo/Kin Cheung, File)
FILE - Hong Kong activist Ben Chung Kam-lun, one of the 47 pro-democracy activists is escorted by Correctional Services officers to a prison van to change to another prison cell in Hong Kong, Friday, March 5, 2021. A Hong Kong court began mitigation hearings for prominent pro-democracy activists who were convicted under a national security law and now face up to life in prison. (AP Photo/Kin Cheung, File)
FILE - Former law professor Benny Tai, a key figure in Hong Kong's 2014 Occupy Central protests and also was one of the main organizers of the primaries, who was arrested under Hong Kong's national security law, gives the thumbs up as he is escorted by Correctional Services officers in Hong Kong March 2, 2021. A Hong Kong court began mitigation hearings for prominent pro-democracy activists who were convicted under a national security law and now face up to life in prison.(AP Photo/Kin Cheung, File)