William has already posted about this case but I’d like to chime in from a slightly different angle. This is just one of many cases that has been overturn as a result of confessions that appear to have been forced confessions. It seems that significant psychological pressure is placed on defendants to confess during the interrogation process. The first case in Japan of a death sentence being overturned occurred here in Kumamoto after it was deemed that the confession had been forced and that the accused, Mr. Sakae Menda, was not guilty:

“Police held Menda for three weeks, without allowing him access to a lawyer, until they extracted a confession. During interrogation, he was starved of food, water and sleep, and beaten with bamboo sticks while being suspended upside down from a ceiling. The police eventually coerced Menda into signing a written statement.”

https://en.wikipedia.org/wiki/Sakae_Menda

Another case that has been in the news is that of Mika Nishiyama. She has not been exonerated but she has been granted a retrial after her confession was deemed to be suspect:

https://www.japantimes.co.jp/news/2019/03/20/national/crime-legal/japanese-supreme-court-oks-retrial-ex-assistant-nurse-2003-murder/#.XJ8P9S2B3Sx

The photo of Mr. Miyata in his wheelchair shows his son, Masahiro, behind him. On one of the news reports I saw, he said something like “it’s good that my father has been found innocent, but what about the people who trumped up the charges against him? When will they be put on trial?” My sentiments exactly.

– Kirk

http://www.asahi.com/ajw/articles/AJ201903290047.html