Q&A: The Magnitsky affair

Sergei Magnitsky died in custody in November 2009

The Magnitsky affair has soured relations between Moscow and Washington, casting a spotlight on corruption in Russia.

It led to US sanctions on a group of Russian officials, retaliation by Russia and the bizarre spectacle of a dead man being put on trial.

That man, the late lawyer Sergei Magnitsky, was found guilty of tax fraud by a Moscow court on 11 July 2013, as was his former boss, US-born investment fund manager Bill Browder. Mr Magnitsky died in prison in 2009 - allegedly after beatings - but Russia dropped an investigation into his death.