The Constitutional Court on Thursday ruled that state employees cannot be punished for engaging in whistleblowing activities against their superiors.
The court based its ruling on the case of two state employees, a police officer and tax inspector who both were fired for criticizing their bosses.
"A state employer might express his opinion (based on real facts) if it concerns public interests and if it is not motivated by an intent to defame or pursue personal goals," said the ruling published on the court web site
The decision was made in favor of Alexei Mukomolin, a police officer from Tolyatti in the Samara region who criticized his superiors in a video statement posted online in 2009.
Soon after, Mukomolin received a warning and, after he staged a picket in protest, was fired from the police force.
The other plaintiff, Lyubov Kondratyeva, a tax inspector from Moscow, was fired after questioning her superiors' travel expenses during an interview on Stolitsa television.
Dmitry Medvedev has made the fight against corruption a hallmark of his presidency, and anti-corruption experts said the court ruling marked a key step in the right direction.
"The fight against corruption would be impossible without this decision being made," said Kirill Kabanov, head of the nongovernmental National Anti-Corruption Committee.
But Kabanov, a member of the presidential commission on human rights, said the court ruling raises further questions because federal law doesn't define "public interest." He said it would be important to include the definition in the law.
The court ruling comes after courts have ruled against the authorities in several high-profile defamation cases.
"I see that there is a growing tendency that courts rule not in favor of authorities, and this is a positive sign," Ivan Starikov, a former deputy economic minister and now opposition leader, told The Moscow Times.
Starikov said he was specifically referring to the case of Kommersant reporter Oleg Kashin, who was acquitted in June of defamation in a lawsuit filed by Vasily Yakemenko, head of the Federal Agency for Youth Affairs and a founder of the pro-Kremlin Nashi youth group. Kashin had linked Yakemenko to an attack that left him in a coma last fall.
In another example, Memorial human rights chief Oleg Orlov achieved a similar victory in June when a court cleared him of slandering Chechen leader Ramzan Kadyrov, whom he had linked to the 2009 killing of rights worker Natalya Estemirova.