The police station at Oimachi has seen better days. In the small interview room, on the third floor, the aging linoleum is scuffed, the bare walls seemingly unpainted during Japan's lost decade.

Officers wandered about the squad room beyond — chattering to their radios, pulling forms from desk drawers — pausing only to acknowledge the 5 p.m. anthem piped over the loudspeaker system. It had been barely 12 hours, but it felt a long way from the pristine arrivals hall at Haneda Airport.

A detective came in and sat down. The two-man patrol explained the detention. This gaijin (foreigner) had committed an offense: riding a commuter train without a passport.