Mam Sonando, the 71-year-old director of Cambodia’s only independent radio station, Beehive Radio, was sentenced to 20 years of prison in a Cambodian court Monday. He was found guilty in inciting a rebellion in the eastern state of Kratie, where he allegedly urged thousands of villagers to take up arms against the Cambodian government.

Sonando, who is also a prominent rights activist and the President of Cambodia’s Democrat Association, was arrested in July at the request of the Cambodian Prime Minister, Hun Sen.

Mam Sonando, director of Cambodia’s Beehive Radio

His trial has sparked outrage in Cambodia with several rights groups claiming the verdict to be politically motivated, and expressing concern that this will have an effect on freedom of speech in the country. Rob Finch, a Senior Consultant at the Cambodian Center for Human Rights, said:

Free speech is being increasingly stifled, and the sentencing of Mam Sonando will not help matters. People will be more afraid to speak out for fear of incurring charges of incitement etc. under the Penal Code and other repressive laws. Free expression is however protected under domestic and international law, so if people are brave enough to continue exercising their rights in the face of this severe government repression, then there is hope yet.

Sok Sam Ouen, the defence lawyer for Sondando and Director of the Cambodian Defenders Project, an organisation providing legal assistance to activists and poor Cambodians, criticised the verdict for being “very harsh” and almost entirely based on supplementary evidence

“He spoke to the villagers for five minutes, and gave them legal advice. That’s it,” he explains.

He believes that there is another reason for the arrest and conviction. In recent years, Mam Sondando has been an outspoken critic of the government’s policy on land resources in Cambodia. As the economy grows rapidly — at an average rate of 5.5 per cent for the past four years — more developers, foreign and national, are laying eyes on the South East Asian kingdom.

A common governmental practice is to grant investors economic land concessions for developing. But the concessions often mean that the people living on the land are evicted; according to civil rights group Adhoc, 400,000 Cambodians have lost their family land since 2003 due to the government policy on land management.

Sok Sam Ouen, Rob Finch and an array of other groups believe that Sonando’s critique of this policy on his Beehive Radio is the real reason he was sentenced.

“Beehive Radio is the most free radio station in Cambodia, and it depends on Mam Sonando. It means a lot to the Cambodians. But it will not run without him, I do not think,” says Sok Sam Ouen.

He did not know whether Mr Sonando would choose to appeal the verdict to the Supreme Court, but added:

“Maybe if he does, they will be less political.”

Anya Palm is a Bangkok-based journalist specialising in South East Asian human rights and politics. She tweets at @AnyaP