A Hong Kong court is set to hand down a sentence to prominent pro-democracy activist Joshua Wong Thursday for his second conviction under a Beijing-imposed national security law that has effectively stifled the city's democracy movement.

Wong, 30, pleaded guilty to conspiracy to collude with foreign forces to endanger national security in September, facing a maximum penalty of life imprisonment. Pleading guilty typically reduces a sentence.

The court hearing is scheduled to begin at 9:30 a.m. Thursday and is expected to last 30 minutes.

The former student leader of the democracy movement was already serving a prison term of four years and eight months after entering a guilty plea in a separate national security case linked to an unofficial primary for the pro-democracy camp.

Critics say Wong’s case reflected the authorities’ determination to keep prominent dissidents behind bars, chilling civic activism.…