Lots of crime goes unreported in Japan, so I've read many times.
If police don't think they can solve a crime? They just toss it, uncounted.
A lot of 'suicides' in Japan are "Clinton-Style" but again if there's no leads? Or corruption? It goes in the books as "suicide by multiple self-inflicted blows to the head" or something.

There's also that whole "cultural shame" garbage, which helps in many things but is harmful in other ways :/