Two years ago today the body of a father of two from Moscow was found face down in a prison isolation cell where he had languished in squalid conditions for more than 11 months. Every year hundreds of people die inside Russian prisons and most go unreported.
But the death of Sergei Magnitsky, a corporate lawyer hired by a British firm to investigate a multimillion-dollar tax scam, lit a fire that has rallied those seeking to end the culture of corruption and impunity among Russian government officials and has caused diplomatic rifts that have reverberated around the world.
Yesterday Mr Magnitsky's mother, Natalia Magnitskaya, travelled to Berlin for the opening of a new exhibition on the death of her son. One of those present at the ceremony was Bill Browder, a millionaire British hedge fund manager, who initially hired Mr Magnitsky as an investigator and has since spearheaded the campaign to bring those responsible for his death to justice.
After two years of relentless lobbying, the American-born British businessman has managed to gather a growing coalition of European and North American nations who – much to the chagrin of the Kremlin – have either brought in visa bans against 60 officials named as complicit in Mr Magnitsky's death or are in the process of passing sanctions against them.
But he remains frustrated at Britain's lack of response, accusing Foreign Office diplomats of being loath to start a fight with their Russian counterparts.
"I've encountered more bureaucratic resistance in Britain than anywhere else," he told The Independent yesterday. "The Foreign Office seems to be primarily interested in maintaining as uncontroversial a status quo as they can. There doesn't seem to be any genuine concern that murderers could come into this country."
In contrast to countries such as the United States, Canada and the Netherlands, Britain has so far resisted any pressure to publicly ban the officials from entering the UK. Earlier this year, after a coalition of 20 US senators took up Mr Browder's cause, the State Department reluctantly announced that 60 officials believed to be involved in Mr Magnitsky's arrest, detention, death and subsequent cover-up were placed on a visa ban list. It was the first time Russian officials had been publicly forbidden from entering the US in 25 years and has sparked a series of tit-for-tat responses from the Kremlin, which has accused Washington of meddling.
Moscow recently announced a blacklist of unnamed American officials involved in "high-profile humanitarian crimes" such as the "indefinite detention of prisoners at Guantanamo Bay and the uninvestigated killings of peaceful people in Iraq and Afghanistan". Last week it emerged that two Russian generals who have been linked to the Magnitsky case pulled out of a planned visit to Washington.
The move has only emboldened Mr Browder's supporters in the Senate who have now tabled a broad human rights bill – named after Magnitsky – which would invoke a travel ban against violators of human rights, freeze any US assets they hold and publish their names. The Dutch and Canadian parliaments have since passed resolutions in favour of tabling a similar bill and Mr Browder believes he has now secured the support of Germany and Poland.
But attempts to pursue successful prosecutions inside Russia have hit a brick wall. Mr Magnitsky was hired by Mr Browder in 2008 to investigate a multimillion-dollar tax fraud allegedly carried out on his businesses by Russian officials working from within the country's powerful interior ministry. His employer had already fallen out with the Kremlin. Mr Browder, who runs the hedge fund Hermitage Capital Management, made millions trading shares in Russian firms following the collapse of the Soviet Union. But he never shied away from speaking out about the corrupt management practices in firms he invested in. By 2005 he had been banned from the country.
Mr Magnitsky spent months investigating a tax scam which cost the Russian taxpayer £144m. When he publicly named the officials he believed were responsible, he was arrested by those he had implicated and kept in appalling pre-trial prison conditions until he died.
Human rights groups – including President Dmitri Medvedev's own human rights watchdog – have said there is ample evidence showing that the 37-year-old was tortured, beaten and denied access to vital medical help. Yet no one has been prosecuted.
"Any façade of legitimacy that the Russians have tried to portray has completely fallen apart," says Mr Browder, whose grandfather used to be the head of America's Communist Party.
But he remains angry that Britain appears to have bought the official line from Moscow that the case is being properly investigated. He says: "I'm a British citizen. Yet it appears that there are a number of civil servants who would rather have Russian torturers and murderers come here than risk a diplomatic furore."
The Foreign Office did not respond to a request for comment.
Timeline: The case
2007 Sergei Magnitsky receives death threats when he uncovers a tax fraud worth £144m, the biggest in Russian history, which implicates politicians, police, judges and members of the Russian mafia.
2008 Magnitsky is arrested by the same police officers he publicly names as being part of the tax scam he uncovered.
2009 Magnitsky dies in prison. Russia's own human rights commission later finds he was refused family visits, was not allowed medical treatment when he fell ill with pancreatitis. Medical evidence suggests he was also beaten.
2010 US Secretary of State Hillary Clinton urges Russia to bring officials responsible for Magnitsky's death to justice. The EU passes a law allowing member states to seize assets held by 60 Russian officials implicated in the crime.
2011 State Department puts 60 officials on visa ban list. Similar plans being sought in Canada, Netherlands and Poland. Britain does not pursue a ban. Two doctors who failed to attend Magnitsky are the only two officials punished. A number of other officials have been promoted.