Three Hong Kong police officers have been found guilty of conspiring with triad members to pervert the course of public justice by tipping them off about an imminent raid on an illegal gambling den four years ago.

The trio’s offence came to light after they unknowingly met an undercover officer infiltrating the Wo Shing Wo triad gang and revealed to him their plan to stage a sham operation in June 2018.

The District Court convicted officers with the three organised crime and triad bureau on Wednesday. Sergeant Chiu Kwong-lam, 56, and constables Lai Fuk-hong, 50, and Fu Yu-man, 38, are facing up to seven years in jail.

Police constable Lai Fuk-hong.

A fourth defendant, Constable Cheung Tsz-kin, 30, was cleared of the charge due to reasonable doubt in the prosecution’s case.

Prosecutors had accused the four of feeding information to the triad gang’s Tsuen Wan faction about a planned raid on a betting establishment inside Tak Fung Industrial Centre on the night of June 22, 2018.

The officers also allegedly plotted to hire “actors” pretending to be gamblers in the den to be arrested.

The undercover agent, who was assigned to work in the gambling den at the time, said he received instructions from the faction leader on June 18 to move most items in the gambling den to a gaming centre in the neighbourhood, leaving only one betting machine on site.

Police constable Fu Yu-man.

Two days later, at the request of the triad boss, the undercover agent met the four officers at Tsuen Wan Police Station, where the defendants purportedly gave instructions on how to make the staged operation look realistic and set the criteria for selecting the right actors for the job.

Police later called off the June 22 operation and arrested the four officers on June 27. A subsequent inquiry found the accused had falsified internal records about the investigation into the illegal den.

The defence sought to challenge the undercover officer’s credibility by citing his alleged violations of internal protocols, including unexcused absence from duty, embezzlement and other criminal activities while he was working for the triad. Lawyers also floated the idea of a conspiracy by the prosecution’s witnesses to frame their clients.

Deputy Judge Katherine Lo Kit-yee, however, found the agent to be an honest and reliable witness, saying his involvement in various crimes during the covert operation was necessary to earn the gang leader’s trust. She also found no reason for the agent and his colleagues to give false evidence against the four officers.

Instead, the judge ruled that Chiu, who led the investigation into the faction, had deliberately delayed the raid at the den in a bid to allow the gang to prepare.

The judge found the sergeant, Lai and Fu guilty based on the words spoken by them and their demeanour during the June 20 meeting, which she said showed their knowledge of the sham operation and intent to pervert the course of public justice.

Cheung, who remained relatively quiet throughout the meeting, was acquitted after the judge found insufficient evidence he had knowingly taken part in the operation.

The three disgraced officers were remanded in custody until sentencing on September 16.

The manager of the gambling den, 39-year-old Chan Siu-po, was sentenced to eight months’ imprisonment last year after he pleaded guilty to the same perversion charge.