Govinda Mainali, now 44, was convicted of killing a 39-year-old woman. But new DNA techniques used to re-examine evidence shows that the semen found inside the victim's body was not Govinda's, and matches that of another person's hair found in the room where she was killed.
The last time I met Govinda was in November 2006 in a jail in Yokohama. At that time he was required to speak in Japanese through an interpreter, but we did manage to sneak in a few sentences in Nepali. He had put on some weight and was balder than the last time I'd seen him five years previously in a detention centre in Tokyo. He was thankful for support from Japanese activists who arranging for family visits as well as defending his innocence.
I asked him if I should keep sending him Nepali magazines because the news from home was so depressing. "Any news from Nepal cheers me up," he had replied.
During both meetings, Govinda convincingly maintained his innocence. He admitted having paid for sex ten days before the murder, but said he had been framed. The woman worked for the Tokyo Electric Power Company by day, and was a prostitute by night.
Now, new DNA techniques not available in 1997, prove that there was another man involved who could be the killer. Govinda's lawyer, Katsuhiko Tsukuda, says the "basis for the conviction has collapsed". Japanese legal experts say there is now sufficient grounds for a retrial because the original court decision had not taken this evidence into account.
In 2000, the Tokyo District Court had acquitted Govinda saying there wasn't enough evidence. But the Tokyo High Public Prosecutors Office requested a remand, and the Tokyo High Court approved it. The High Court later found him guilty, and the Supreme Court upheld the ruling sentencing him to life imprisonment in 2003. The police was under pressure to make an arrest in the high profile case, and reportedly suppressed evidence.
A group of Japanese set up the 'Justice for Govinda Innocence Advocacy Group' that is struggling to keep the case alive and to prove his innocence. Over the years, the pressure group has regularly flown in Govinda's wife, Radha, his mother, brother and two daughters to Tokyo to visit him in prison to keep his morale up.
I asked Junko Hasumi of 'Justice for Govinda' the reason why her group had taken up the case so relentlessly. "Most of our members have never been to Nepal," she replied, "they are involved because they know there has been a miscarriage of justice, and it is to draw attention to the need to reform Japan's judicial system."
Govinda's case has become headline news in Japan again, with regular follow-ups in the mainstream newspapers and television. All major stations covered the visit last month by Radha and Govinda's brother, Indra Mainali, to the Yokohama prison.
On return to Kathmandu, Radha told Nepali Times: "I had been living like a widow these past 15 years, our daughters haven't been able to grow up with their father. But for the first time there is hope."
When he saw Radha in prison last month, Govinda thought she had come to get him out. "But his morale is high and he is convinced that he will be acquitted soon," she added.
Indra Mainali says his brother was puzzled about why he still needs to be in prison. "He is worried that he will not be able to see our mother who is in frail health," he said.
Govinda's defence team say there is precedence from recent acquittals based on new DNA evidence in other murder cases in Japan, and lawyers are confident the High Court will accept retrial.
The Japan Federation of Bar Associations also came out publicly in support of a retrial based on new evidence because of recent cases of innocents being incarcerated. It has accused prosecutors of withholding key evidence that would exonerate the accused. The Federation's Keita Miyamura told the Japanese media there were serious questions about miscarriage of justice and called for judicial reform: "We must create a system under which all evidence is disclosed."
In 2001, Japanese activists took me to interview Shinichi Sano, the author of a book on Govinda, Tokyo Electric Power Co. Office Lady Murder Case. After visiting Govinda in prison and traveling to Ilam to meet his family, Sano was convinced of Govinda's innocence.
He told me he wrote the book to expose Japan's judicial system and the hidden tensions within Japanese society. "In Japan we have a saying: when something is rotten, cover it up," he said. "And that is what happened, the truth was so ugly we tried to cover it up and have a fall guy from a poor country that didn't dare make a fuss take all the blame."
1994: Govinda arrives in Japan from Ilam and works in an Indian restaurant in Chiba
March 8, 1997: 39-year-old woman is killed in a Tokyo flat, body found a week later
March 23: Govinda arrested and initially charged with overstaying and then with murder and robbery
April 2000: Tokyo District Court acquits Govinda
December 2000: Govinda gets life sentence from Tokyo High Court
October 2003: Supreme Court upholds verdict
March 2005: Mainali files appeal for retrial with high court
21 July, 2011: Yomuiri Shimbun breaks story on prosecution suppressing new DNA evidence
26 July: Defense submits retrial request to Tokyo High Court
4 August: 'Justice for Govinda' and the Nihon Kokumin Kyuuenkai petition the Tokyo High Public Prosecutors Office to release Govinda
2 September: Prosecutors disclose to defence team that there are 42 additional items of evidence for DNA tests
8 September: Defence team learns saliva on victim was Type O blood (Govinda's blood type is B), protests suppression of evidence
12 September: Govinda's wife Radha and brother Indra visit him in prison amidst heavy media coverage
16 September: Prosecutors say saliva test result is insufficient ground for retrial
"Living like a widow", Photo essay by TAKAAKI YAGISAWA
Something that he never did, SHINICHI SANO in TOKYO
A Japanese author writes an impassioned plea for justice in the case of Nepali serving life imprisonment for murder in Tokyo