Demoralized by low pay, long working hours, and abusive superiors, the police major recorded two video clips appealing directly to Prime Minister Vladimir Putin to crack down on police corruption.
The videos, which highlight a mounting Russian tendency to turn to the Internet for justice, have become a media sensation.
They have already been viewed by more than 1 million people on the video-sharing site YouTube. And although the videos cost Dymovsky his job, they have inspired others to follow his lead.
Two more former policemen on November 11 posted personal videos on YouTube urging President Dmitry Medvedev to improve conditions for Russia's troubled police.
In one, former traffic policeman Vadim Smirnov complained that he was forced to resign after joining a trade union. Hours later, former police Major Mikhail Yevseyev posted a video claiming two innocent men were sentenced to life in prison following a 2005 act of arson in the northern Russian city of Ukhta that killed 25 people.
Chekalin, who resigned from his post to protest the arson charges, says his online video appeal is "the only way" to inform the president about the case after law enforcement agencies blocked all his attempts to clear the convicted pair.
"I just want to be heard, heard by you and by the public," he tells Medvedev in the clip. "Don't leave things like that; it will end badly. I can be muzzled. Yevseyev, Dymovsky, anyone can be muzzled. But in the end, all this will lead to very, very dire consequences."
Videos on the Internet appearing to document Russian police abuse are nothing new. What makes these video clips unique is that they come from identified insiders and are addressed directly to Russia's leaders.
Russians, disillusioned by their country's dysfunctional police and courts, are increasingly relying on the Internet to seek justice.
In recent years, disgruntled citizens and professional rights campaigners alike have successfully battled injustices after launching support campaigns on blogs and social-networking sites such as LiveJournal or the Russian version of Facebook, "Vkontakte."
Just over one-third of Russians have regular access to the Internet, but that number is growing fast. Russians are currently the world's second-largest group of users of LiveJournal.
One of the highest-profile online campaigns to date was that in support of Svetlana Bakhmina, a former lawyer for the fallen Yukos oil company. The mother of three had been jailed on tax evasion charges that were widely viewed as political.
"It was one of the first political successes of bloggers and Internet users," says Yury Vassiliev, who reports on Internet and media issues for RFE/RL's Russian Service. "The Internet community can undeniably be credited with the fact that Bakhmina, who was pregnant at the time, had her baby not in a prison in Mordovia but at a hospital close to Moscow and for the fact that she was then freed instead of returning to prison."
Valery Balikoyev, the man behind the now-famous website in support for Bakhmina, understands better than anyone the Internet's lobbying power.
Emboldened by his success, he recently launched another site -- girus.ru, short for Civic Initiative in Russia -- on which people can create and sign petitions demanding improvements in health care, education, ecology, or even animal rights.
"It's obviously much easier for people who want to collect signatures for petitions to do so online, with e-mails and a registration system confirming signatures, than in the street with a piece of paper," he says.
Other Internet lobbying successes include the campaign to save the European University in St. Petersburg, which had been abruptly closed down on charges that it breached fire-safety regulations. After a massive petition campaign, the case drew media attention, prompting St. Petersburg Governor Valentina Matviyenko to step in and reverse the closure.
In 2008, a cardiology center offering free treatment to patients in the city of Tarusa, south of Moscow, was shut down by local officials. After a LiveJournal petition gathered thousands of signatures, the clinic was reopened and the officials were sacked.
The Internet has also grown into an indispensable tool for Russia's civic and human rights groups, particularly in reaching out to people spread across Russia's vast territory.
Activist Vyacheslav Lysakov says his car owners' lobby group could simply not function without the Internet.
"Without it, we could not exist offline," he says. "Our first protest action was organized via the Internet in four days. In four days, we were able to bring together about 50 regions and stage a demonstration. This would have been impossible without the Internet. Thanks to the Internet we united; thanks to the Internet we communicate almost around the clock."
His blog-based movement, Freedom of Choice, organized nationwide car rallies in 2006 to protest the jailing of Oleg Shcherbinsky, a railway worker sentenced to four years in jail after being wrongly accused of causing a road accident that killed the governor of the Altai region.
The rallies were instrumental in helping Shcherbinsky win his appeal and walk free just weeks after the rallies.
Landmark Victories Or Isolated Cases?
Critics say that these are isolated victories and that thousands of others have been unable to draw attention to their plight through the Internet.
"How many people wanted to complain to Medvedev about an injustice and were never heard?" asks Anton Nosik, a Russian Internet pioneer and executive of the Sup company, which owns LiveJournal in Russia. "Isolated cases like these clearly cannot solve problems on a national scale."
But veteran rights activist Svetlana Gannushkina says each of these successful online campaigns raises the Internet's profile as a crime deterrent.
"Even if there are only a few cases in which we were able to influence the situation, it means there are dozens or hundreds of other cases in which people will stop short of committing violations in order to avoid such Internet campaigns," she says.
The impressive array of websites operated by the Kremlin also testifies to the Internet's growing role as a social and political force.
Medvedev himself runs a blog on LiveJournal, as well as an official video blog, a personal website with family photos, a site for children, and his own YouTube channel. Even his wife, Svetlana, has her own official website.