She will be sentenced next month.
Chen was accused of taking part in a riot on August 31, 2019, when protestors set up roadblocks with debris in Wan Chai and clashed with police. In 2020, a District Court judge ruled that she had no case to answer. The Department of Justice then lodged an appeal, leading to the retrial.
In her ruling, Deputy District Judge May Chung said Chen chose not to leave the scene even though she clearly knew that it had turned into a dangerous riot.
The judge said the defendant kept shouting false accusations against the police while they were dispersing protesters, prompting others to stick around and continue confronting officers.
Chung said the only reasonable explanation is that Chen intended to participate in the riot and encourage other people to engage in actions that undermined social order.
Chen had pleaded not guilty and said she was trying to mediate.
She did not testify in the latest trial.
The 48-year-old is now on remand, and the court has been adjourned until April 3 for mitigation and April 9 for sentencing.
