Hong Kong's top court on Tuesday allowed three young democracy activists the opportunity to appeal their prison sentences over their roles in pro-democracy protests in 2014.

Chief Justice Geoffrey Ma of the Court of Final Appeal gave the green light to Alex Chow, 27, Nathan Law, 24, and Joshua Wong, 21, citing points that merit further discussion, such as the motivations behind their acts, local broadcaster RTHK reported.

An appeal hearing for the three was scheduled for Jan. 16.

After their "unlawful assembly" convictions in August last year, Chow served a suspended prison term, while Law and Wong served community service orders.

But a year later, they were given prison terms between six and eight months by the Court of Appeal after the Justice Department appealed their initial sentences.

"The Court of Appeal set a very strict ruling on defining assembly that's not peaceful," Law told the press before entering the court. "By appealing the result of the Court of Appeal, we could really get a better ruling on the sentencing concerning the incident or concerning the cases on unlawful assembly."

Law and Wong had been released on bail last month to appeal their prison sentences. Chow, who did not join them in applying for bail then, was released Tuesday.

"I think I also have to thank (Secretary for Justice) Rimsky Yuen for providing a platform to give us or the people of Hong Kong a lot of opportunities to let justice not only be done but also to be seen," Chow said.

Yuen had reportedly pushed for imprisonment of the trio in what has been criticized as being politically motivated move.

The authorities have stressed that the activists committed an unlawful act, the "serious nature" of which could only be reflected in prison terms.

But the move has prompted concerns among politicians, academics and lawyers from countries including the United States and Britain, who cast the three activists' treatment as political prosecution.

Thousands of people occupied the streets and brought part of the territory to a halt for 79 days in 2014 to protest China's restrictive electoral reform plan drafted for Hong Kong's future leader, which was described as "fake universal suffrage" by the pro-democracy camp for it would grant Beijing's favored candidates the public mandate.