Four people were given three-month prison terms on Wednesday for attacking disqualified lawmaker Nathan Law at the airport in January.
The three men and a woman, aged between 53 and 72, were convicted at West Kowloon Magistracy of common assault and taking part in an unlawful assembly. A second woman was found not guilty of the offences.
Law had told the court that he was punched and kicked by a group of pro-Beijing demonstrators when he arrived back in Hong Kong after attending a political forum in Taipei.
He was besieged by about 20 to 30 people, who shouted words like “traitor” and “running dog” at him.
Law also had some kind of liquid thrown at him during chaotic scenes that were filmed by the media. He suffered relatively minor injuries in the attack.
All four of the convicted; Giok Kheng, Tong Fat-cheung, Kwong Kwai-sim and Lau Pit-chuen were released on bail pending appeals.
Another defendant in the trial, Lam Kam-sheung, was acquitted of the charges against her, after photos and video footage failed to prove she was at the scene when the attack happened.
Magistrate Edward Wong described the case as serious. He noted that the group wanted to express their political views, but said their action had disrupted social order, and put Law and security guards in danger.
Law, who was disqualified as a legislator for failing to take his oath properly, is currently on bail as he appeals against a prison term relating to a protest in 2014.