Unable to make any progress at a national level, Öcalan appealed to the European Court of Human Rights, which accepted the case in November 2000. In March 2003, the ECHR delivered a verdict stating that Öcalan was not tried by an independent and impartial court but dismissing claims that his detention conditions were inhumane or that his detention in Kenya violated his rights. Following an appeal, the Grand Chamber of the ECHR ruled that Turkey had violated articles 3, 5, and 6 of the European Convention of Human Rights by refusing to allow Öcalan to appeal his arrest and by sentencing him to death without a fair trial in 2005.
On his detention in Kenya by Turkish authorities, Öcalan reasoned Art. 5 of the ECHR was violated since Turkey did not possess jurisdiction in Kenya, nor was he able to challenge his extradition. He also didn’t accept to be seen as a terrorist, that his extradition a lawful cooperation between two states in their fight against terrorism nor that the way he was brought to Turkey was in accordance to Art. 3 of the ECHR. The court found that in lack of jurisdiction no rights were violated during his detention in Kenya since a Kenyan police officer drove Öcalan towards the Turkish airplane and Kenyan and Turkish authorities appeared to have cooperated without having an extradition treaty in place. Regarding the involvement of a military judge in the trial which was defended by Turkey as a civilian judge has eventually replaced the military before the sentence was delivered, the ECHR maintained that the court sentencing Öcalan should have been independent at all times and it did not matter on what stage of the trial the military judge was replaced. Following the ECHR ruling, Öcalan’s requested for a retrial in Turkey in 2006, which was refused by Turkish courts in 2007 on grounds that a retrial would not alter the verdict.