British athlete Dwain Chambers (C) arrives at the High Court in central London, on July 9, 2008. Dwain Chambers has started court proceedings against the British Olympic Association (BOA) in a bid to enable him to compete at next month's Beijing Olympics.The 30-year-old is currently banned from competing at any Olympics by a BOA bylaw which prevents all those found guilty of doping offences representing the country at a Games, even if they have served a drugs ban, unless they can prove "mitigating circumstances". AFP PHOTO/Shaun Curry (Photo credit should read SHAUN CURRY/AFP/Getty Images)