Hong Kong (AFP) - A former Hong Kong lawmaker was jailed Wednesday for exposing an anti-graft probe into a senior police officer's handling of a mob attack on democracy protesters in 2019.
Lam Cheuk-ting was found guilty of three counts of revealing that Superintendent Yau Nai-keung was being investigated by the Independent Commission Against Corruption (ICAC).
Hong Kong law forbids revealing the identity of anyone being probed by the anti-corruption watchdog.
Magistrate Jacky Ip handed Lam four months in jail, ruling that he jeopardised an investigation and public security.
Lam, who pleaded not guilty, said he would appeal and told the court he had "no regret about going on trial", according to local media.
Yau was a police commander in Yuen Long -- an area bordering mainland China -- when a group of men attacked democracy protesters returning from rallies.
Live footage of the white t-shirt dressed mob beating people in a train station -- combined with the police's response -- became a watershed moment during the 2019 protests.
Lam was among those wounded in the bloody chaos.
Yau led a team of police officers into a village next to the train station where many of the white-clad men were filmed retreating.
After a search, Yau told reporters that no arrest was made and that he saw no one carrying weapons.
The police's response further hammered public trust in the force and fuelled accusations of police-triad collusion.
Police said their officers were busy dealing with large-scale protests elsewhere and denied any suggestion of collusion.They have since recast that night's incident as a fight between evenly matched opposing sides.
Three months after the Yuen Long attack, Yau was assigned to lead the police's investigation into the incident.
In response, Lam disclosed the ICAC investigation into Yau "out of consideration of public interest".
"I would rather ring the bell too loud than to leave it inaudible to anyone," he told the court.
Before he became an opposition lawmaker, Lam used to be an ICAC investigator himself.
An ICAC officer summoned to the witness stand during the trial confirmed there had been an investigation.But Yau has never been arrested or charged and it is unclear whether the probe is ongoing.
Critics and rights groups said Hong Kong police routinely used excessive force during the 2019 protests.
Hong Kong's police watchdog exonerated the force and no officers have lost their jobs over the handling of the unrest.
In July last year, a Hong Kong court jailed seven government supporters for their involvement in the attack.
Like most of Hong Kong's prominent democracy activists, Lam is facing multiple prosecutions but Wednesday's verdict was his first jailing.
He was detained last year and charged along with 46 others under a sweeping national security law Beijing imposed on Hong Kong to stamp out dissent.
