Generally speaking, most foreigners are treated pretty well in Japan. Sometimes shamefully well. However, legally the Japanese police can engage in behavior towards foreigners that would qualify as discrimination in most other democracies. This happens more frequently in some places than in others. I’m told that the Tokyo police, under the instruction and tutelage of the ultra-nationalist governor Ishihara, can be particularly difficult to deal with, routinely stopping foreigners on their way to work for a “random” I.D. check. In Kyushu, this behavior seems to be less pronounced, though in recent months two Saga ALTs (possibly more?) have been stopped for no reason other than their obvious non-Japanese ancestry. In both cases, the police were polite and the whole episode lasted less than five minutes, just enough time to check the ALT’s gaijin card before diving into the topic of Chicago’s two baseball teams. A minor inconvenience really.
Nevertheless, some foreigners are rightfully upset at this treatment since most of us were invited here on the behest of the Ministry of Education. While there is little that can be done to overturn this legally-sanctioned conduct, being informed does help. Activist, journalist and full time Japan resident Aruduo Debito has created a wonderful summary of foreigners’ rights under Japanese law when dealing with the police and anyone else asking for ID. In the meantime, try not to look foreign.