Debunking Japanese dual-nationality myths with code

Every single post on Japan-related subreddits that mentions someone is binational will have a bunch of commenters jump in to say it’s illegal, OP needs to hide it or they will be made to renounce as soon as they turn 20. While this is true for people who naturalized to a foreign nationality, it’s patently false for dual-citizens by birth.

Bi-nationals by birth must select one of the nationalities upon reaching 20, but if they select Japan, there is no requirement to renounce the other citizenship unless they assume public office.

Article 16(1)A Japanese citizen who makes the selection declaration must endeavor to renounce their foreign nationality.

(2)In cases where a Japanese citizen having made the selection declaration and not having lost foreign nationality assumes the post of a public employee (with the exception of a post that may be assumed by a person not having the nationality of that country) at their own discretion, the Minister of Justice may pronounce a judgment of loss of Japanese nationality if it is found that the assumption of the post is markedly contrary to the purport of the selection of Japanese nationality.

Source

“must endeavor to renounce” is very different from “must renounce” and there are no provisions for failing to renounce outside of the public office case.

When you point this out to the posters, they will invariably bring up the case of Naomi Osaka who very publicly chose her Japanese nationality to participate under the 日の丸 flag at the Tokyo Olympics. Many sports publications articles claim she thus renounced her US citizenship but there has never been any actual announcement directly from her to that purpose.

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Okay, so where does the coding come up you might ask? Well it was pointed out to me that US citizenship renouncement is a heavy process. There are many forms to fill and hefty fees to pay. Most importantly, all renouncements are published in the Federal Register under the title Quarterly Publication of Individuals, Who Have Chosen To Expatriate (see an example here). So let’s see if we can find Naomi in these publications.

The Federal Register has a very good API available without any registration required, so there’s no need to fiddle with web scraping. Our python script is very simple:

import requests

url = "https://www.federalregister.gov/api/v1/documents.json"

querystring = {
    "fields[]": ["title", "raw_text_url", "document_number"],
    "conditions[type][]": "NOTICE",
    "per_page": "500",
    "conditions[term]": "Quarterly Publication of Individuals, Who Have Chosen To Expatriate",
}

response = requests.request("GET", url, params=querystring)

for item in response.json()["results"]:
    publication = requests.get(item["raw_text_url"])

    try:
        publication.raise_for_status()
    except requests.exceptions.HTTPError as e:
        print(f"Error downloading {item['document_number']}: {e}")
        continue

    # Save the publication text to a file
    with open(f"data/{item['document_number']}.txt", "w") as f:
        f.write(publication.text)
        print(f"Downloaded {item['document_number']}")

Running this will download a text file version of all matching publications from 1997 to today in the /data folder. Now all we need to do is to recursively search for OSAKA in the downloaded files with grep -ri OSAKA data/

Unsurprisingly, this does not bring any results, nor with her father’s name LEONARD. Therefore, unless there is a way for celebrities to opt out of having their name published in the government gazette, she has not renounces her US citizenship, despite her very high profile, because she does not have to.

Hang around for the next chapter of this exploration where I will use ChatGPT to see if we can extract some interesting info from this data.