First up, the labor unions (i.e. the ones that let non-Japanese join, even help run). Their annual marches in March, for example, have made it clear to the media (and employers like Nova) that non-Japanese (NJ) workers are living in and working for Japan and that they are ready to stand up for themselves, in both collective bargaining and public demonstrations.
These groups have gained the ear of the media and national Diet members, pointing out the legal ambiguity of trainee visas, and systematic abuses of imported labor such as virtual slavery and even child labor. For example, Lower House member (and former prime ministerial candidate) Taro Kono in 2006 called the entire work visa regime “a swindle,” and opened ministerial debate on revising it.
In the same vein, local NGOs are helping NJ workers learn the language and find their way around Japan’s social safety net. Local governments with high NJ populations have begun multilingual services; Shizuoka Prefecture even abolished their practice of denying “kokumin hoken” health insurance to non-Japanese (on the grounds that NJ weren’t “kokumin,” or citizens).
These governments are holding regular meetings, issuing formal petitions (such as both the Hamamatsu and Yokkaichi “sengen”) to the national government, recommending they improve NJ education, social insurance, and registration procedures.
Still more NGOs and concerned citizens are petitioning the United Nations. Special Rapporteur Doudou Diene has thrice visited Japan on their invitation, reporting that racial discrimination here is “deep and profound” and demanding Japan pass laws against it.
Although the government largely ignored Diene’s reports, United Nations representatives did not. The Human Rights Council frequently referenced them when questioning Japan’s commitment to human rights last May. That’s how big these issues can get.