Theary Seng, center, a Cambodian-American lawyer gestures as she enters the Phnom Penh Municipal Court, in Phnom Penh, Cambodia, Thursday, Nov. 26, 2020.
Theary Seng, who has long been one of the most outspoken critics of Hun Sen and his government, is one of the best known defendants living in Cambodia.
Hun Sen has been in power for 35 years and has often been accused of heading an authoritarian regime.
On Wednesday, the U.N. human rights expert on Cambodia expressed serious concerns about the trial.
“The mass trials of CNRP activists appear to be politically motivated, lacking clear legal grounds and constitute a serious violation of the due process rights, firmly established by international human rights law,” said Rhona Smith.