Like many other foreigners here, I have had my brushes with the Japanese justice system, from ID checks by cops wanting to practice their English to one memorable appearance on a witness stand. I have also seen it in action as a moviegoer, from prison comedies (Yoichi Sai's "Keimusho no Naka [Doing Time]" being the funniest) to courtroom dramas (Yoshi-mitsu Morita's "39 Keiho Dai Sanjukyujo [Keiho]" being the most mind-twisting).
One lesson that I have learned from these experiences and observations is that the Japanese are a law-abiding people for a very good reason -- once the system here has you in its grips you are well and truly in the meat grinder. True, safeguards exist for the accused, who are entitled to a defense lawyer, but the legal scales are tipped in favor of the police and prosecution, who want to save face by convicting as many "criminals" as possible -- and nearly always succeed.
Meanwhile, before and during their trials, prisoners and their supporters are reminded, through a thousand rules, exactly who has the power and who has been stripped of every particle of individuality and will.