Honestly, I wouldn't count on it. The Japanese criminal justice system is actually terrifying.So I suppose he's trying to strongarm the PM of Japan into letting return to the US to serve his sentence in a US prison. Considering the US prison system, might be better off in a Japanese prison tho. Or maybe just let the dude off once here.
I think the moment that clicked for me was researching the 1995 Tokyo sarin gas attack and realizing that there were actually two. Prior to the attack on the subway, the same group released sarin in a suburban neighbourhood as a test run. The reason this isn't common knowledge is that the police arrested some random guy and abused him until he falsely confessed that he accidentally caused the incident by mixing household chemicals..
When you're so determined to look like you're doing your job that you end up literally covering up a terrorist attack by white-torturing the shit out of some random guy.