A Russian court's conviction of a dead man, Sergei Magnitsky, made headlines this past week because the case was so bizarre.

But Kremlin critics say it's just one in a string of recent prosecutions in which President Vladimir Putin's government is using the courts to silence whistle-blowers and muzzle dissent.

"If you've decided to stay in Russia, you need to be ready for [your] arrest," Ilya Yashin, an opposition leader, wrote on the news website Svobodnaya Pressa, or Free Press.

His advice included tips on how to prepare a backpack with towels and slippers for the first few days in jail. The material was directed at people who recognize themselves in an online gallery of grainy images from the May 6, 2012, anti-government demonstration at Bolotnaya Square in Moscow. The event started peacefully but ended in clashes between protesters and police.

More than two dozen people now face charges of attacking the authorities and participating in "mass riots" that day in what's come to be known as the Bolotnaya affair.

Multiple Cases

And there are plenty of others who may need to heed Yashin's advice.

Aleksei Navalny, a high-profile opposition figure and anti-corruption activist, is accused of embezzlement. A related case had previously been scrapped for lack of evidence. He denies the charges and has vowed to continue fighting against what he described as the "feudal regime" in Russia.

"If anyone thinks that myself or my colleagues will cease our activity because of this trial or the Bolotnaya trials or the many other trials going on all around the country, they are gravely mistaken," Navalny told the court on July 5.

The prosecution is seeking a six-year prison sentence, which would halt Navalny's run for mayor of Moscow in September. Given the 99 percent conviction rate in Russia's court system, a guilty verdict seems all but certain.

Navalny likened the trial to a TV series designed to tar him in the court of public opinion. According to a survey by the Levada Center, an independent polling organization, about half of the Russian people have heard about his case and 44 percent of these people believe the goal is to silence Navalny and his supporters.

Among those who have heard of the Bolotnaya case, nearly 60 percent say it is designed to intimidate the opposition.

"They want to show the public that OK, if you are protesting against us, well, we are coming to you, we are arresting you," Maria Baronova, a defendant in the case, told NPR.

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