Former world chess champion and opposition leader Garry Kasparov (L, front) arrives to attend a court hearing in Moscow August 24, 2012. Kasparov was detained during the trial of three members of the Russian punk band Pussy Riot outside a court building on August 17 and was later summoned to appear before court, according to local media. REUTERS/Sergei Karpukhin (RUSSIA - Tags: POLITICS CRIME LAW CIVIL UNREST ENTERTAINMENT)