HONG KONG—The first person convicted under the national-security law imposed by Beijing was sentenced to nine years in prison Friday, in a case closely watched as a bellwether for how strictly Hong Kong judges will enforce the law.
Tong Ying-kit, 24 years old, had been found guilty Tuesday of inciting secession and committing terrorist activities. During street protests on July 1 last year—the anniversary of the city’s handover from British to Chinese rule and the day after the law took effect—he drove a motorcycle that collided with police officers. He was carrying a flag bearing the popular protest slogan “Liberate Hong Kong, Revolution of Our Times,” which the local government later declared has forbidden pro-independence connotations.
“This overall term should sufficiently reflect the defendant’s culpability in the two offenses and the abhorrence of society, at the same time, achieving the deterrent effect required,” a panel of…