The trial of punk band Pussy Riot is reminiscent of the Inquisition, according to Mikhail Khodorkovsky, the jailed oil tycoon who is Russia's most famous political prisoner.
In his first comments on the case, Khodorkovsky called on Russians to support the three women, on trial on charges of hooliganism motivated by religious hatred, for their anti-Putin performance in Moscow's official cathedral.
The trial showed that Russians have been "deprived of an honest and independent judiciary, of the opportunity to defend ourselves and to protect people from lawlessness", he wrote in a statement published on his defence team's website on Monday.
"The word 'trial' is applicable here only in the sense in which it was used by the inquisitors of the middle ages," he said.
The case against Pussy Riot, marred by procedural abnormalities and carried out at unprecedented speed, is expected to wrap up this week.
Khodorkovsky said he believed the court had been ordered to issue a verdict during the Olympics, "while the world's mass media are busy with other things".
At the end of a one-day visit to the London Olympics last week, the Russian president, Vladimir Putin, called on the women not to be judged "too severely". They face two to seven years in prison.
The trial is being heard in the same courtroom where Khodorkovsky was tried on a second round of charges in 2010. Once Russia's richest man, Khodorkovsky was arrested in 2003 as he began to pose an increasing political challenge to Putin. He was convicted of fraud and tax evasion in 2005 and of money laundering and embezzlement in 2010, cases he has called politically motivated.
Writing from his cell in a remote penal colony in northern Russia, Khodorkovsky said it was "painful to watch" the trial of Pussy Riot, recalling his own days inside the glass cage that holds those being prosecuted in room seven of Moscow's Khamovnichesky court.
The cage, he said, was a "subtle and sophisticated way of mocking people" who had complained about the Russian practice of trying defendants in barred cages. "In the summer you feel like a tropical fish in the glass cage," Khodorkovsky wrote.
He described the "humiliating body searches … where you have to strip naked" before entering court.
He urged supporters to gather at the courthouse. "Every smile of support … is worth its weight in gold," he said. "I call on all thinking, educated and simply good and kind people to send words of hope to the girls. Your support – the support of every person – is now very important to those who have ended up in confinement of the will of evil forces."
