The High Court on Wednesday overturned the conviction and sentence of a university student accused of hitting a mainland student.
Chan Hoi-man had been given a nine-and-a-half month prison term for assault occasioning actual bodily harm.
Video footage showed that during a public forum at the University of Science and Technology in November 2019, the mainland victim was surrounded and assaulted by a group of people wearing face masks.
Chan was arrested more than four months later.
A pair of glasses, trainers, a black knitted bracelet and an iPhone found at his home were presented as evidence during the trial, and the magistrate agreed that they were "extremely similar" to those of one of the assailants.
However, High Court judge Albert Wong said these items are commonly found in the market, and the fact that Chan was found to have such things, four months after the incident, was not enough to confirm that he was one of the perpetrators.
"After carefully inspecting the evidence, I also think the chances are not small that the appellant was the assailant. But based on the reasons given above, it is hard to be at ease that the magistrate's conviction ruling was safe and sound," the judge wrote in his judgement.