Japan-born half-Korean barred from public function

[Maciamo]

Japan Times : Promotion just for Japanese: supreme court

The Supreme Court on Wednesday overturned a high court ruling and supported the Tokyo Metropolitan Government's decision to bar a civil servant from taking a managerial promotion exam due to her South Korean nationality.
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In her lawsuit, Chong, a second-generation South Korean resident born to a Korean father and Japanese mother, argued that the metro government's stance violates the constitutional principle of equality before the law and freedom to choose one's occupation.
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Chong was hired in 1988 and became the metro government's first foreign public health nurse after the central government abolished in 1986 a regulation qualifying only Japanese nationals as public health nurses. She was promoted to chief level in 1992.

I would say that this is discrimination. However I don't understand why this person born and raised in Japan and with a Japanese mother would want to keep her Korean nationality, while she is perfectly eligible to become Japanese, and what is more probably had to choose between the Korean and Japanese nationality at the age of 20 (as minors normally have both parents' citizenship).

What is more alarming is this :

It is the first Supreme Court ruling on promotion discrimination based on nationality.
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The decision, handed down by presiding Supreme Court Chief Justice Akira Machida, is likely to affect other local governments' policies on the promotion of employees with foreign nationalities, who still face hurdles due to a government policy requiring Japanese citizenship for civil servants in areas of public authority.
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"The Tokyo Metropolitan Government unilaterally banned foreigners from all managerial positions," he said. "In a local government such as the Tokyo Metropolitan Government, where many people engage in a diverse range of tasks, there is no rational reason for having all managerial positions filled by Japanese nationals, regardless of the nature of the job."
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"The Supreme Court has no idea of what postwar democracy is," she said. "I want to tell everyone in the world not to come to Japan. Working in Japan as a foreigner is the same as becoming a robot that pays taxes."

Although no foreigners were allowed to become public health nurses before 1986 (de facto 1988), there is to be a reversal of policy toward foreigners looming with this kind of decision from the Supreme Court (not to mention the hards-stance against foreigners taken by the governor of Tokyo, who the Japanese like so much that they re-elected him).