Chow served as vice chairwoman of the Hong Kong Alliance, an alliance that organized annual marches and vigils to commemorate the 1989 Tiananmen Square protests. On June 4, 2021, Chow was arrested for promoting an unauthorized assembly on the 32nd anniversary of the protests. She was released on bail one day later, but was later arrested again on June 30. After being denied bail many times, Chow it was eventually granted, under the condition that she paid bail in cash, she handed over all travel documents, and she would not hold a BNO passport. On 13 December, she was sentenced to 12 months in prison over the banned 2020 vigil. On 4 January 2022, she was jailed for another 15 months over the banned 2021 vigil; the judge ordered 10 months of the sentence to be served consecutively with the December sentence, meaning that Chow was to spend a total of 22 months in jail. [1]

On 14 December 2022, Chow won an appeal against her 15-month sentence over the banned 2021 vigil. The presiding judge said in a written statement that police "did not raise measures or conditions to be considered" in order to let the vigil take place during the pandemic.

Although one of the charges was dropped, she remains in prison for her other two charges. [2]