Joshua Wong, Nathan Law and Alex Chow were jailed in August past year for their role in the 2014 Umbrella Movement mass pro-democracy protests, after Hong Kong's government pushed for harsher sentences.
A panel of five judges sided with Joshua Wong, Nathan Law and Alex Chow in their appeal against monthslong prison terms for unlawful assembly.
A lower court had originally given Wong and Law community service orders and Chow a suspended sentence.
The protest sparked the "Umbrella movement," which pushed for full democracy in Hong Kong and brought parts of the city to a standstill for three months.
Mabel Au, director of Amnesty International Hong Kong, said the court had corrected an injustice.
Invalidating the sentences of imprisonment imposed by the Court of Appeal and reinstating those imposed by the magistrate, the court warned [press summary] that there is a new appellate guidance now in place from the Court of Appeal: "future offenders involved in large scale unlawful assemblies involving violence will be subject to the new guidelines rightly laid down by the Court of Appeal".
Hong Kong, a former British colony, returned to Chinese rule in 1997 with a guarantee of wide-ranging freedoms, including an independent judiciary and freedom of speech, but critics accuse Beijing of creeping interference in the city's affairs and the government of toeing the Beijing line. The trio were released on bail in October and November previous year pending their appeal. "At the same time it's not the time for any congratulations or celebrations". He also said the road to democracy in Hong Kong will be bumpier in the future because the "Reclaim Civic Square" initiative was deemed violent and the standards for civil disobedience was tightened. "In such a case involving violence, a deterrent sentence may be called for and will not be objectionable on the ground that it creates a "chilling effect" on the exercise of a constitutional right".
"Maybe more and more activists will be locked up because of this harsh judgment", Wong, 21, told reporters on the courthouse steps after the decision. He said the fight for democracy would continue.
The trio were granted bail after being jailed for more than two months, then filed an appeal to The Court of Final Appeal.
Last week a dozen US lawmakers nominated Wong, Law, and Chow along with Hong Kong's entire pro-democracy movement for the Nobel Peace Prize, in an effort to recognize what they said were peaceful efforts to bring political reform to Hong Kong and uphold its rule of law and human rights. "This is setting a precedent".