The new law enacted by the Diet to prevent human rights abuses in the workplace comes on the heels of the Health, Labor and Welfare Ministry's disclosure that nearly 3,700 businesses employing trainees from abroad violated labor laws and work safety rules in 2015. But it alone is unlikely to end the practice in nursing care and other strategic fields where demand exceeds supply.

At least that has been the experience in the United States, whose alleged shortage of workers in technical fields has resulted in pressure to lift the cap on the number of H-1B work visas. Although billed as an immigration issue, the real reason is to control labor costs. According to a study by the U.S. Citizenship and Immigration Services, 27 percent of H-1B workers were paid less than the prevailing wage.

Violations of labor laws pertaining to foreign workers are rampant in both Japan and the U.S. But whistleblowers are reluctant to come forward out of fear that doing so will jeopardize their legal status and future employment opportunities. It's a legitimate concern in these precarious times, since guest workers often come from countries where wages are lower.