Gambia's High Court has sentenced the former information minister to life imprisonment for conspiring to overthrow the ruler of 17 years with T-shirts demanding an end to dictatorship.
Amadou Janneh, who also holds a U.S. passport, was convicted of treason after a seven-month trial.
Judge Emmanuel Nkea told a crowded court Tuesday that witnesses had proved "beyond reasonable doubt" that Janneh and three co-accused were "conspiring among themselves" by printing T-shirts that demanded "End to Dictatorship!"
The other three were sentenced to three years' imprisonment.
President Yahya Jammeh took power in a coup and is to be inaugurated Thursday following disputed November elections
He has drawn international criticism for claiming he can cure AIDS with an herbal body rub.