Human rights — Fair trial — Right to hearing before independent and impartial tribunal — Principle that no man should be judge in his own cause — Scope and application — Judge an unpaid director and chairman of charity linked to Amnesty International — Amnesty International campaigning against torture and in favour of trial of persons responsible for torture irrespective of status — General Pinochet — Hearing before House of Lords regarding request for extradition of General Pinochet on charges of torture — Amnesty International given permission to intervene — Whether judge automatically disqualified — Decision of House of Lords set aside and new hearing ordered — The law of England