The Meshchansky district court also sent Aidar Gubaidullin's case back to prosecutors on September 18 "to remove the obstacles hindering a trial."

"The qualification of Gubaidullin's actions do not correspond to the charge, his right to a defense was violated as it was not clear to him what exactly he was accused of," the judge said.

Earlier in the day, a prosecutor at the trial asked the court to change pretrial restrictions for Gubaidullin and return the case to the prosecutor’s office "for clarifying the essence of the charge."

Gubaidullin told journalists after leaving the courtroom that after spending time in custody "I look at people around me differently."

"People outside do not even realize what kind of system of milling and breaking souls and destinies the prosecutors, investigators, courts, and jails are. It is a huge system and every part of it is connected with the other, and nobody inside it cares much about justice," Gubaidullin said.

Gubaidullin’s release came as a surprise to his brother, Ildar, who said the advocacy campaign to free actor Pavel Ustinov as well as others imprisoned during the recent Moscow protests may have played a role.

"Nobody expected the judge to rule this way," he said. "I think the campaign by actors and [other] high-profile people could have made an impact, including in the release of Aidar."

The 25-year-old programmer’s mother said she lived in fear the whole time her son was under arrest.

"Our life after the arrest turned completely upside down," said Galya Gubaidullin, who was able to see her son once during his 40-day imprisonment. "My attitude toward everything that has happened has changed a lot. Everything turned evanescent. It became scary to live, frightening for my children and grandchildren."

Gubaidullinwas arrested on August 9 and initially charged with taking part in mass disorder, which, according the Investigative Committee, took place on July 27 during unsanctioned rally to protest the refusal by election officials to register independent and opposition candidates for September 8 elections to the Moscow city council.

His charge was changed later to attempted assault of a law enforcement officer with a plastic bottle.

Students of Gubaidullin's alma mater, the Moscow Physics and Technology Institute, have held a series of individual protests, demanding his immediate release.

In all, 17 people were arrested and charged with attacking law enforcement officers during the rally. Some of them have been convicted already, while some have been released.

Human rights activists insist that events during the July 27 rally were not "mass disorder."

The Moscow-based Memorial human rights center recognized Gubaidullin and eight other people arrested in the case as political prisoners.

Gubaidullin's sudden release comes amid protests in Moscow against the imprisonment of actor Pavel Ustinov, who was sentenced to 3¹/₂years in prison for violence against police during a similar rally last month he insists he did not participate in.