Drugs? Petty crime? Homelessness? No other country comes close to managing these problems as well as Japan does, and Japan somehow manages to do this without descending into a 1984-esque surveillance state. Wander the streets of Tokyo at night and you will see zero drug-addicted homeless people. How many western cities could one say that about?
The Western mentality, especially in the USA, focuses on independent will. The government is not supposed to stop people from making choices that are bad for society or bad for themselves. In Japan, the mentality is that every person has an obligation to work with society and to fit in at all costs. The Japanese criminal justice system exemplifies that spirit, but it touches all areas, such as employment, personal relationships, behavior in public, talking to strangers, etc.
In short, if you want to have the advantages of Japan, you need to take it with the disadvantages as well.
It is definitely possible to hold people in detention without torturing them while also getting acceptable results.
The fact that many people opt to falsely plead guilty and get a reduced punishment in a society that highly values honor and saving face should say a lot about it.
There is something about seeing drug addicted zombies impossibly contorted in on themselves and swaying in the wind that appears very inhuman to me. If given the choice, pre zombification, of a false confession or life as a zombie I know which I would chose.