Pro-democracy activist Ken Tsang Kin-chiu has been convicted by the Kowloon City Court of one count of police assault and two of resisting arrest during the Occupy movement in 2014.
But he was acquitted of two other charges of resisting arrest.
Principal magistrate Peter Law Tak-chuen said on Thursday that he was convinced beyond reasonable doubt that Tsang was the one who poured an unknown liquid over 11 police officers and subsequently resisted arrest by two others who were undoubtedly executing their duties.
He explained that the act of splashing liquid no doubt amounted to an assault given the hostility involved, and that Tsang must have known he would be arrested in the aftermath, yet resisted the arrest.
But Law accepted that his resistance may in part have been due to a natural reaction towards pepper spray and hence acquitted him on two counts of resisting arrest.
Sentencing is scheduled for Monday afternoon.
Three letters have been submitted in mitigation. Tsang previously had a clean criminal record.
The case centred on one of the most controversial nights of the 79-day civil disobedience protests, when thousands of Hongkongers occupied thoroughfares in Admiralty, Central, Causeway Bay, Mong Kok and Tsim Sha Tsui to demand universal suffrage.
The verdict was delivered a week ahead of that for a sister case at the District Court, where seven police officers will stand trial next Wednesday for allegedly assaulting Tsang on the same night.
Eleven police officers had told the court that liquid that smelled like urine was spilled on them as they were clearing protestors from Lung Wo Road underpass in Admiralty on October 15.
A statement from police sergeant Wong Hoi-man said: “We were moving forward when I suddenly felt my head was wet ... I looked up to see a man wearing goggles and [a] face mask pouring an unknown liquid.”
But Wong did not identify his attacker, except to say that it was “a man in black wearing goggles and [a] face mask”.
The court also heard from sergeant Butt Wang-tat, who testified that he immediately tackled a man in black after seeing him pour liquid from a one-litre bottle onto the underpass below, but said he struggled to bring the man down to the pavement.
Sergeant Ching Ying-wai added that he needed to pepper-spray the man’s face in order to restrain and handcuff him.
Tsang did not take the stand or call witnesses in his defence after denying one count of police assault and four of resisting arrest.
His identification was a major point of contention during the trial as the defence argued that Tsang was not the man in videos filmed by police – which showed a man in black T-shirt, goggles and mask splashing liquid – or ATV footage of a man in a black T-shirt being arrested.
Also at issue was the authenticity of the ATV videos admitted after a trial within a trial, as the defence contended that the court must be sure beyond a reasonable doubt that the footage had not been tampered with.
Police assault and resisting arrest are both punishable by two years’ imprisonment, under the Offences Against the Person Ordinance.
Tsang was earlier swarmed by a hundred supporters and journalists as he arrived at Kowloon City Court.
Sporting his usual navy suit with a bright yellow ribbon pinned to his lapel, the social worker greeted cameramen and photographers while his Civic Party vice-chairwoman Tanya Chan and lawmaker Kwok Ka-ki stood next to him in support.
Civic Party lawmaker Alvin Yeung Ngok-kiu, League of Social Democrats lawmaker “Long Hair” Leung Kwok-hung and activist Tsang Kin-shing were also among those who stood by his side.
Before he entered the building, Tsang shook hands with his supporters, who raised yellow umbrellas and a banner that read: “Plaintiff turned defendant, prosecuted after he was beaten.”
Some also chanted: “Civil disobedience. Shame on political prosecution.”
Those who wished to hear the verdict in person were given stickers at 1.30pm to reserve a seat in courtroom number 13, where the press had been allocated 28 spots and the public, 74.
Others occupied the benches at the floor lobby to await news of the anticipated court ruling.