Almost immediately after Naomi Osaka’s victory at the U.S. Open, speculation began to swirl in both traditional and social media about the 20-year-old’s reported dual-national status, given that dual citizens of Japan by birth are supposed to decide upon one or other nationality by the age of 22.

Whether the users, writers or bloggers were dabbling in borderline racist ideology or wholeheartedly endorsing multiculturalism, many appeared to be in agreement on at least one issue: In two years Osaka would be forced to forfeit her American citizenship in order to remain a Japanese citizen.

But is Osaka’s apparent predicament as straightforward as many netizens make out? Does the law “force” you to choose?

While Japan’s Nationality Act nominally forbids citizens from having more than one nationality, the “choice” facing those with multiple nationalities is less clear-cut than many believe.

Below are the basic facts of the law and how it is enforced — or, in this case, how it isn’t.

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Is it illegal to have dual nationality?

The answer to this question is complex, thanks to the murkiness of the law, and depends on factors such as the age of the dual national.

Yasuhiro Okuda, a law professor at Chuo University who specializes in the Nationality Act, says that while under the law one must declare a single citizenship, this doesn’t equate to the government forcing Japanese citizens to forfeit dual citizenship.

“For those who have become dual citizens, they must choose, but there is no penal regulation,” Okuda said, pointing out that the failure to choose citizenship is closer to a breach of contract than an outright illegal act.

So the bottom line is that the legality of dual nationality is effectively academic, as long as the law lacks any penalties or mechanisms to force citizens to choose a single nationality.

Has anyone been stripped of their dual nationality by the Japanese government?

There have been no reported instances of dual nationals by birth having their citizenship revoked.

In April, the Justice Ministry confirmed to The Japan Times that the justice minister had never issued a warning to a dual citizen by birth to decide upon one nationality, meaning that no such dual national has ever been stripped of their Japanese citizenship under Article 15 of the Nationality Act.

This lack of enforcement is a fact that Okuda says is often overlooked.

“For athletes like Naomi Osaka, the newspapers write under the impression that she must choose a nationality,” he said, “but many people do not know that (the Justice Ministry) has never warned people (for not declaring one nationality), although in the past the Justice Ministry has reportedly mailed the children from international marriages a notification about the obligation to declare one nationality.”

However, for those who have naturalized to other countries, there have been a few reported cases of citizens being stripped of their Japanese passport.

The Nationality Act states that Japanese citizens who naturalize to a foreign country will automatically lose their Japanese nationality upon obtaining foreign citizenship.

Why does the Japanese government not enforce the law?

According to professor Okuda, “from the initial creation of this nationality system, the Justice Ministry thought it would be impossible to issue warnings” to those who failed to declare one nationality, yet it was created simply because “the Justice Ministry did not want to recognize dual citizenship.”

If the law is not enforced, why does it exist?

If the goal is to discourage citizens from having dual citizenship, figures suggest the law is not completely useless. Although enforcement is nonexistent, an increasing number of dual nationals are forfeiting their Japanese nationality.

From 2013 to 2017 the annual number of cases of dual nationals forfeiting their Japanese citizenship increased from 380 to 770, Justice Ministry data shows.

Another reason the law has survived is that changing it would entail a delicate discussion about immigration and identity that many Japanese politicians would be eager to avoid.

How do you choose Japanese nationality?

There are two ways to choose Japanese citizenship, the Justice Ministry website says: You can either provide proof that you have forfeited your non-Japanese nationality or simply turn in a form to your local municipal office declaring your Japanese nationality.

To clarify: You can choose Japanese citizenship without providing any evidence that you have forfeited your other nationality.

However, people who have declared their Japanese citizenship are legally obliged to “try” to relinquish their non-Japanese passport. Scholars claim that the current law allows this level of leniency partly out of consideration for dual nationals of countries that do not allow their citizens to forfeit citizenship.

Media reported in late 2017 that the number of people who declared Japanese citizenship topped 3,000 for the first time in fiscal 2016, reaching a record-breaking 3,368 people.

How many Japanese citizens hold multiple nationalities?

The Justice Ministry confirmed to The Japan Times in April that some 890,000 are in a position to be dual nationals, according to data from local municipalities from the years 1985 to 2016. This number includes those who have declared or forfeited Japanese citizenship, as well as those that are assumed to have multiple nationalities based on their birthright.

The “Has anyone been stripped of their dual nationality by the Japanese government?” section was edited on Oct. 3 for clarity. The Justice Ministry website on how to choose Japanese citizenship is here. ENGLISH/information/tcon-01.html. Your questions and comments: lifelines@japantimes.co.jp

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