http://search.japantimes.co.jp/print/fl20090324zg.html
Punishing foreigners, exonerating Japanese
Debito Arudou sees growing evidence of judicial double standards
By DEBITO ARUDOU
But the bias goes beyond cops and into criminal prosecution, with Japanese courts treating suspects differently according to nationality. We've already tackled the subject of how judges discount testimony from foreigners (Zeit Gist, Aug. 14, 2007), but here's the emerging pattern: If you are a Japanese committing a crime toward a non-Japanese, you tend to get off lightly. Vice versa and you "haven't a Chinaman's chance," as it were....
...So let's summarize: If you're a foreigner facing Japan's criminal justice system, you can be questioned without probable cause on the street by police, apprehended for "voluntary questioning" in a foreign language, incarcerated perpetually while in litigation, and treated differently in jurisprudence than a Japanese...
...Feeling paranoid? Don't. Just don't believe the bromide that Japanese are a "peaceful, law-abiding people by nature." They're actually scared stiff of the police and the public prosecutor. So should you be. For until official government policy changes to make Japan more receptive to immigration, non-Japanese will be treated as a social problem and policed as such.