Nerve-Gas Guru Tests Japan Legal System

This undated file photo shows doomsday cult guru Shoko Asahara, who was sentenced to hang for trying to bring down Japan's government in an elaborate scheme culminating in a nerve-gas attack on Tokyo's subways that killed 12 people and sickened 5,000 on March 20, 1995. (AP Photo/ Kyodo News, File) (AP)

The ministry has no record of any such case in the past, Tsuji said.

If Matsui's petition fails, Asahara will join 84 people on death row. He would likely be hanged at the Tokyo Detention Center where he is now incarcerated, but officials said that decision will not be made until after the ruling is announced.

Chizuo Matsumoto _ he assumed the religious name Shoko Asahara when he created Aum _ was convicted and sentenced to die in April 2004.

In their verdict, the three judges held that "These crimes are the most heinous and grave that we have ever seen," and that "there is no other punishment for him than death."

By age 30, Asahara's life had etched an amazing trajectory.

After two run-ins with the law in his 20s that led to convictions for misdemeanor fraud and assault, he gave up a massage and yoga business to found a cult preaching an eclectic mishmash of Buddhist, Hindu and New Age teachings.

It was a huge success: Within a decade of its creation in 1984, it had swelled to 10,000 members in Japan and claimed another 30,000 in Russia. It was generating tens of millions of dollars in income from membership donations _ thousands of followers gave up all their possessions to live on Aum communes _ and from a booming computer software business.

But as it grew into Aum Shinrikyo, aka Aum Supreme Truth, it became increasingly focused on hastening the world's end.

Critics and "deserters" were treated harshly _ nearly a dozen were murdered, authorities later discovered, some incinerated at the Aum commune.

The cult actively recruited members with scientific and medical backgrounds, and used their expertise to set up labs to manufacture various chemical and biological weapons _ from anthrax to the deadly nerve gas sarin, developed by the Nazis in World War II _ and stockpiled guns and hallucinogenic drugs.

Court documents say the cult was also seeking uranium to use in a "dirty bomb" nuclear device.

Asahara told his followers Armageddon was near and only his followers would survive. According to his former aides, Asahara grew afraid police were onto Aum after newspapers linked it to a 1994 nerve gas attack in the central Japan city of Matsumoto that killed seven people.