A 19-year-old in Hong Kong has been convicted of sedition for writing anti-government graffiti in a commercial building toilet, violating the city’s

domestic national security law.

West Kowloon Court on Wednesday rejected a defence psychiatrist’s opinion that a congenital mental disorder prevented Leung Kai-lok from understanding the offensive words he used against the government and police.

Leung, 19, stood trial earlier this year before a magistrate hand-picked by the city leader to oversee national security proceedings.

He pleaded guilty to three counts of criminal damage but denied committing a seditious act, an offence under the Safeguarding National Security Ordinance.

The trial heard that the defendant scrawled graffiti inside a men’s toilet in China Hong Kong City in Tsim Sha Tsui between July 17 and 21, 2025. The toilet was located on the same floor where the defendant worked as a part-time clerk at the city’s Vanuatu consulate.

Surveillance footage showed Leung leaving the toilet at around 4pm on July 17 shortly before a cubicle was found with a statement urging former city leader Carrie Lam Cheng Yuet-ngor and her successor John Lee Ka-chiu to die.