Unfortunately, in Japan the police are more interested in confessions than in actually securing any evidence. The lengths they will go to in order to secure "confessions" is relatively well documented (just one relatively thorough article on the subject here: http://www.iht.com/articles/2007/05/07/news/japan.php)

So to me, and to anyone who knows about the Japanese legal system, a "confession" isn't really worth that much. I'd rather the police actually have evidence. If they have that, I'd be more confident that they got the right person.

More on Japanese forced confessions: http://news.bbc.co.uk/2/hi/asia-pacific/7063316.stm

Only one step away from being employed by a company to automatically remove any audio or video without DRM written on it.

I can't think of any reason to do this otherwise.