The Supreme Court on Friday rejected a special appeal by lawyers for Aum Shinrikyo founder Shoko Asahara, finalizing the death sentence for the man who masterminded the cult's horrific nerve gas attack on the Tokyo subway system in 1995.

The top court's Third Petty Bench, led by Justice Yukio Horigome, affirmed that Asahara, who is nearly blind and incapable of communicating with his lawyers, is legally sane and can thus be held responsible for his actions.

The decision, which is likely to generate legal controversy, concludes the trial of the 51-year-old mass murderer, which has dragged on for more than a decade.