HONG Kong’s highest court has overturned prison sentences for three young pro-democracy activists convicted over their roles in 2014’s Umbrella Movement protests in the city.

A panel of judges sided with Joshua Wong, Nathan Law and Alex Chow in their appeal against prison terms for unlawful assembly.

The case sparked controversy because a magistrate initially gave the three lenient sentences, but the justice secretary requested a review that resulted in prison time ranging from six to eight months, raising concerns about judicial independence and rule of law.

The Court of Final Appeal’s ruling was an unexpected victory for the city’s youthful opposition movement after recent setbacks.

But the activists said they feared it would have a chilling effect on future protests because the five judges on the panel also said they endorsed the lower court’s view that a new, tougher sentencing approach was needed for unlawful assemblies.

“Hong Kong is on the whole a peaceful society and elements of disorder and violence must be deterred,” chief justice Geoffrey Ma said.

Wong, 21, said after the decision: “Maybe more and more activists will be locked up because of this harsh judgment.”

The three were convicted on unlawful assembly charges for their part in storming a courtyard at government headquarters in September 2014 in protest at Beijing’s plan to restrict elections.

Wong, Law, 24, and Chow, 27, had already served about two months of their sentences before they were bailed for their appeal.

The 2014 protests spawned a youthful opposition movement that gained political traction but also faced resistance from Hong Kong’s Beijing-backed government.

Law was elected to the semi-democratic legislature in 2016 but was disqualified after a government legal challenge. Wong also had plans to run for office but the prison sentence had barred him from office for five years.

Wong may still end up behind bars. He is also appealing against a three-month prison sentence for a separate contempt case.