A Moscow court sentenced Lebedev, a member of the opposition Left Front movement, to prison for discussing plans to overthrow Russian President Vladimir Putin with the alleged help of Georgian leaders, state news agency RIA Novosti reports.
Left Front leader Sergei Udaltsov is facing 10 years in jail for his role in the plot. He's tied to a plot "aimed at organizing mass disturbances in Russia" with Georgia leader Givi Targamadze, a revolution leader.
U.N. special justice envoy Gabriela Knaul this week expressed concern about the independence of the judicial system in Putin's Russia.
"I am concerned that the appointment of judges by the president of the Russian Federation may expose them to political and undue pressure," she said in a statement.
Putin in November signed a measure that expands the definition of treason to include activity that poses a threat to Russia's "constitutional order, sovereignty and territorial and state integrity."
This week, Human Rights Watch published a report critical of the "crackdown on civil society" in Russia.
Putin told Echo of Moscow radio that comparisons between his government and Josef Stalin's was off the mark.
"Stalinism is connected to the cult of personality, massive legal abuses, repressions and (labor) camps," he said. "There are no such things in Russia, and I hope they will never happen again."