They were charged under Ethiopia's controversial anti-terrorism law and convicted last month. All but one received prison terms of five and a half years. Two were journalists working for a Muslim radio station.
The state-affiliated Fana Broadcasting Corporate, citing the court ruling, said Tuesday that the 20 defendants also were found to be "participating in a movement to secure the release of another Muslim group that was under detention."
Muslims have long felt marginalized in Ethiopia and have carried out a number of protests since 2011. Some were met with force, and many protest leaders were jailed.
"The defendants didn't get a fair trial. In fact, we didn't expect the court to give a fair verdict," Mustafa Safi, the defendants' lawyer, told The Associated Press. "They were subjected to both a mistrial and a bad treatment at the infamous Kilinto detention center. They were even unable to pray there. But we will appeal the sentencing anyway."
The defendants had been trying to secure the release of a group of Muslims that had formed to counter government interference in their religious affairs but was detained on terror-related charges. Five members of that group were pardoned in September.
Ethiopia, a strong security ally of the West, is often accused of stifling dissent and jailing opposition groups and critical journalists. The country is currently under a state of emergency declared in October following widespread anti-government protests demanding greater political freedoms.
© 2017 The Associated Press