Oleg Orlov, co-chair of the human rights group Memorial, went on trial in Moscow Thursday over criticism of Russia's Ukraine campaign, which could see him jailed for up to five years.
Since the beginning of the offensive, the Russian government has heightened its repression with an array of legislation, including laws against discrediting the army.
"I do not plead guilty... I'm being tried for my opinion" Orlov, wearing a light grey suit, said in court.
"In my opinion, launching troops into Ukraine undermines peace and international security, and goes against the interests of Russians citizen," Orlov noted.
The defence submitted several requests to cancel the judicial proceeding, but the court rejected all of them. The next hearing is set on July 3.
Before the beginning of the audience, Orlov held up his fist in a sign of defiance, and showed journalists a book titled "The End of Regime" by Alexander Baunov, on the fall of European dictatorships.
He was charged with repeatedly discrediting Russia's military over lone pickets against the Ukraine offensive and over an op-ed in French publication Mediapart titled "They wanted fascism, they got it," which he posted in Russian on Facebook.
A crowd that came to support Orlov applauded as he left the court room.
Orlov began thanking them, but was interrupted by police officers shouting, ordering citizen to get out.
He was accompanied by Nobel Peace Prize winner Dmitry Muratov, who was allowed by the court to join his defence team.
- 'I regret nothing' -
In a speech to journalists, Muratov said that Orlov was being tried "for observing the Russian Constitution" which, he argued, guarantees freedom of expression.
Since sending troops to Ukraine in February 2022, Russia has sought to silence domestic critics and civil society organisations.
"Some may tell themselves that it is better to be silent. But my entire previous life and my position obliged me not to be," Orlov told AFP in an interview on the eve of the trial.
He said his defence would fight the "idiotic charges" but held no illusions on the outcome of the trial.
"The verdict will be guilty, no one has any doubt about it," Orlov told AFP, wondering how harsh the sentence would be.
"I regret nothing, I will say that to the court."
His organisation established itself as a key pillar in civil society by preserving the memory of victims of communist repression and campaigning against rights violations in Russia under President Vladimir Putin.
It had been dissolved in 2021 just months before Putin sent troops to Ukraine.
In March, charges of "rehabilitation of nazism" were brought against Memorial employees.
bur/jmm
