Although it has historical roots in the ancient Chinese and other legal systems, contemporary Japanese Law is a civil law (as opposed to common law) system similar to that of France or Germany.

The Six Codes of Japanese Law

The core of Japanese statutory law is composed of the so-called “Six Codes” (?? ropp?). The six codes consist of:

1. the Civil Code (?? Minp?, 1896)
2. the Code of Civil Procedure (????? Minji-sosh?-h?, 1996)
3. the Penal Code (?? Keih?, 1907)
4. the Commercial Code (?? Sh?h?, 1899)
5. the Code of Criminal Procedure (????? Keiji-sosh?-h?, 1948)
6. the Constitution of Japan (????? Nippon-koku-kenp?, 1946)

Family Law in Japan

Japan’s family law system has been the source of some international controversy. Under Japanese family law, joint child custody terminates together with the marriage. If the husband and wife cannot agree upon child custody as part of an amicable divorce resolution, it will fall the Japan’s family law courts (the ????? Katei Saibansho) to determine custody of the child. The Katei Saibansho are thought to show a strong preference to granting custody to the mother.

Divorce

Japan law distinguishes between four types of divorce, each with varying repercussions:

• Kyogi Rikon: Divorce by mutual agreement
• Chotei Rikon: Amicable agreement cannot be reached, divorce through mediation in a family court
• Shinpan Rikon: Amicable agreement cannot be reached, mediation fails, divorce through decision of the family court
• Saiban Rikon: All options including family court fail, the case then moves to a district court for a decision.

Japan Law Resources

University of Hawaii Paper on Child Custody and Visitation in Japan
English translation of Japanese Civil Code

Introduction to the Koseki Family Registration System in Japanese Law

The Koseki plays a central role in Japanese Family Law — it is your birth certificate, death certificate, marriage license, and census information all rolled into one.

What is the Koseki?

The koseki is the Japanese system of Family Registration, by which births, deaths, marriages and divorces of Japanese nationals are recorded.  Since a koseki is only for those with Japanese citizenship, non-nationals will not have their own koseki, but will only be added to a Japanese citizen’s koseki where appropriate, such as in the case of a Japanese national marrying a foreigner. However, foreign nationals living in Japan are required to register births and deaths of family members with the local city office.

The koseki has its roots in the ancient Chinese system of government, and has been used in Japan for over 100 years. This single document is nothing less than a system of national identity registration, marking any and all changes in family composition and identity, and it thus plays a central role in matters of family law and other interactions with the government. Specifically, the koseki will be used to record the birth of children, marriage and divorce, and the death of a family member. Such events are legally effective only when recorded in the koseki.

Information recorded in the koseki

• family name and given name
• date of birth
• parents’ names and relationship
• date key events such as marriage, death, adoption, etc.
• links to any prior koseki
• official residence (honseki chi)

(Law of Family Register, (???), article 13.)

The koseki contains many important aspects of family identity. For example, the koseki will indicate a head of household (in the right hand column of the document), as well as the family’s official “home” (honseki chi). When a Japanese family member included on a koseki marries, they will secede from that koseki and start a new koseki where they are listed as head of household (or partner). The new koseki will reference the name of the parent family koseki from which they seceded, as well as the honseki chi where the koseki is located. These two pieces of information are usually what’s necessary when wishing to locate a particular koseki, as officially the koseki document resides with the local government offices in the family’s honseki chi.

When a Japanese marries a citizen of another country, the Japanese family member will always be listed as the head of household, and the spouse will be listed as an addition to the family. Traditionally everyone listed on the koseki has to have the same family name, but Japan does allow for either partner to change their last name to that of the other partner.

Koseki and Child Custody Issues

Until the time at which they are ready to start their own family, a child does not have their own koseki, but is instead listed on that of his or her parents. However, if the parents get divorced, the child’s register will move to the koseki of the person with shinken (legal child custody in a divorce). Of course, since a non-Japanese does not have a koseki, if the non-Japanese partner is able to obtain legal custody of a Japanese child, they will need to secede the child from the koseki of the Japanese parent, and start a new koseki just for the child. Although it may seem like a formality to take care of documents if the courts have already granted custody, because of the centrality of the koseki in Japanese family law, it is very important to take these steps. Should the Japanese parent later violate the custody agreement and abduct the child, pursuing the proper legal channels necessary to demonstrate that the Japanese parent does not have custody will be greatly facilitated by the child having seceded from the Japanese parent’s koseki.

Koseki Related Laws and Regulations

See our Japanese Family Law section.

Due to the sensitive nature of the information in a koseki, one of the primary concerns of related law has been the privacy of the koseki information, and discrimination based upon information contained in the koseki. Traditionally the koseki has been treated with a high degree of respect and confidentiality. It is generally not required in order to obtain government services or used as identification or in order to verify residency.

As a result of problems with discrimination based upon the sensitive information contained in the koseki, Japan since the 1970s has moved to protect against such abuses. For example, since 1970 some details of each koseki member’s birth address is no longer included on the koseki. Later regulations forbid employers from asking job applicants to share their koseki document. More recently, a law enacted in May, 2008 restricted access to the koseki to the persons listed on the koseki, as well as anyone who requires the information on the koseki in order to exercise their due legal rights. Individuals who have seceded from a koseki (eg, as in the case of divorce) are also eligible to obtain a copy of the koseki.

In order to obtain a copy, you will need the name of the koseki as well as the honseki-chi where the koseki is located. You can appear at the local government offices to request a copy in person, or contact the authorities to request one by mail. Your lawyer can also obtain a koseki on your behalf if the legal proceedings involve someone listed on the koseki.

More information on the restrictions on who can access the kosekican be found in this article.

Glossary of Terms

Jyuminhyou

The koseki is often confused with the jyuminhyou. However, the jyuminhyou is Japan’s system of residency registration, whereas the Koseki pertains to family-related information.

Hittousya

The head of household, listed on the far right of the koseki.

Honseki-chi

The honseki-chi or honseki is the official “family home”, which confusingly is not necessarily the same as the family’s current residence. Rather the honseki-chi is thought of as the traditional home of the family, often it is one’s birth place or where one’s family maintains the strongest roots– often ties going back hundreds of years. The honseki-chi is particularly important as it dictates which municipal office stores the koseki. City officials often have the last say in determining who has a right to access the koseki. However, it is possible to move the koseki to a new city, and some families will choose to do so. The koseki will include a list of the cities where the koseki was previously held, so you can still track down the current location of a koseki if you know the prior honseki, although doing so will take more than a little bit of bureacratic wrangling, and therefore may be better handled by a competent child custody lawyer.

Koseki touhon

Koseki shouhon

These two terms refer to two different formats for the koseki. The koseki shouhon is like an executive summary of the koseki, and lists only the key facts such as date of birth, parents, place of birth etc. The Koseki touhon is a copy of the entire koseki.

Koseki Fuhyou

Jyouseki touhon

These terms refer to a previous koseki which is no longer valid because it has been superseded by a new koseki. Sometimes you will need to obtain the koseki fuyhou to get information not included on the new koseki.

A straightforward introduction to the law surrounding Japanese citizenship, intended for foreign-born individuals wondering if they qualify for Japanese citizenship, those struggling with dual citizenship/ nationality issues, as well as people looking to emigrate to Japan.

Japanese Citizenship Requirements

Most countries confer citizenship either by birth (as in the US, one becomes a citizen by virtue of being born in the US), or by blood (one becomes a citizen by virtue of having one or more parents who are citizens, also known as Jus sanguinis).

Japan is a Jus sanguinis state, meaning that the critical factor in determining citizenship is your heritage (having parents who are Japanese), and not where you were born.

There are three ways you can qualify for Japanese citizenship:

1. One or both of your parents is a Japanese citizen at the time of your birth.
2. Your father was a Japanese national, but died before your birth.
3. You were born on Japanese soil to parents who are stateless or of unknown nationality.

How to get Japanese Citizenship (Naturalization)

Don’t meet any of the above requirements? You may still be able to get Japanese citizenship through naturalization. Naturalization is the process whereby a long-term foreign resident can become a citizen of their host country.

In Japan, the requirements for naturalization are:

• You must be at least 20 years old.
• You must have resided in Japan for at least five years.
• “Upright conduct”, ie a history of good behavior.
• Has never been part of an organization that has plotted to overthrow the government of Japan.
• Financial resources and wherewithal (employable, etc.) to be able to support yourself.
• You must be stateless, or willing to renounce your existing nationality.

Note that the last requirement is necessary because it is not allowed to have Japan Dual Citizenship.

Applying for Japanese Citizenship

Once you meet all of the above requirements for Japanese Citizenship, your application must be submitted to the Japanese Ministry of Justice. Even if you meet all of the aforementioned requirements, acceptance is never a foregone conclusion.

If you’re interested in obtaining Japanese Citizenship, you should first make sure that you are familiar with all aspects of Japan Law. In many aspects Japanese law (and some argue, Japanese society) is unfriendly to foreigners, providing them with unequal treatment and prejudice. You should be aware of what you’re getting into.

Additional Reading on Japanese Citizenship

• Japanese Ministry of Justice Laws on Citizenship and Nationalization
• English website of the Japanese Ministry of Justice
• Comparison of Japanese and USA systems of Naturalization

What to do if you can’t get citizenship but want to live in Japan

If you’re just interested in living in Japan, you don’t need to acquire Japanese citizenship in order to live in Japan. Most foreigners who live in Japan (even those who live there for a long time) are in Japan legally under a residency permit.

There are various types of residency permits depending upon the purpose and duration of your stay. In general they are granted for things like tourism, study, work, or for the spouse of a Japanese citizen.

Since a complete discussion of Japanese Residency Permits is beyond the scope of this article, I’ll just point you towards a few of the more helpful resources out there:

• Overview of some types of Japanese Residency Permits
• Detailed look at permanent residency in Japan (equivalent of a US Green Card)

In contrast to the United States and many other countries, Japan takes a stricter view of individuals holding more than one nationality (dual citizenship). Since the situations and laws can easily become a bit complex, we’re going to provide a bit of context to help paint a clear picture:

How do you get dual citizenship?

So, how does one come by dual citizenship in the first place? Dual citizenship occurs when one person acquires nationality (and hence, passports, the sign of national identity), from more than one country. This can happen when a child is born of parents of mixed nationality, or of parents who are living in a country other than that of their citizenship.

An example may help: a child born of a German mother and an American father living in America would have dual citizenship (German and American), assuming the parents took the trouble to apply for the German citizenship in Germany (the US citizenship comes automatically for someone born in the US).

Dual Citizenship in Japan

Therefore, a child born in Japan of mixed parents would be eligible for both Japanese citizenship and the citizenship of their foreign parent (for most countries). However, when the child becomes an adult, the picture would look a bit different…

Restrictions on Dual Nationality in Japan

Unlike many countries who tolerate (but don’t officially endorse) dual citizenship, Japan chooses to actively crack down on the dua citizenship. Thus, when a Japanese national holding a foreign nationality turns 20, they will be required to choose one sole citizenship (Japanese or foreign) within 2 years (ie, before the age of 22).

Moreover, a Japanese national who acquires an additional citizenship after the age of 20 would be required to choose a single citizenship within two years of acquiring the additional citizenship.

For complete details you should contact the Japanese Embassy or Ministry of Justice in order to read the full text of the law.

Here is an excerpt from an English translation of the Japanese law on dual citizenship, courtesy of the Japanese Embassy in the USA:

WHO MUST CHOOSE A NATIONALITY
According to Japanese law, for dual nationals there is a specific period of time within which one must choose one’s nationality.  As regards the acquisition of dual nationality, there are the following five examples: 

•   A child born to a Japanese citizen father or mother and a mother or father from a country that allows transmission of citizenship by a parent of either gender (for example, France). 

 

• A child born to a Japanese citizen mother and a father from a country whose laws provide for transmission of citizenship only through the father (for example, Korea). 

 

• A child born to a Japanese citizen mother or father, or two Japanese citizen parents, in a country whose laws provide for acquisition of citizenship by birth in that country (for example, the United States). 

 

• A child of a Japanese citizen who is legitimated by a foreign father’s declaration of paternity (for example, Canada), by a foreign parent through adoption (for example, Switzerland), or through marriage to a foreigner (for example, Switzerland). 

 

• People who have acquired Japanese nationality through naturalization, or by filing a declaration of acquisition of Japanese nationality, but who did not forfeit their former foreign nationality, must also choose which nationality they wish to hold. 

HOW TO CHOOSE YOUR NATIONALITY
For Japanese citizens holding a foreign nationality, below are listed the methods for declaring a single nationality.  When the time comes to choose one nationality, think carefully and then make your decision known by one of the following methods.

ABANDONING YOUR FOREIGN NATIONALITY
Based on the applicable foreign law, submit to the nearest city, ward or town office, or to a Japanese Embassy or Consulate abroad, the form Gaikoku Kokuseki Soositu Todoke, showing your abandonment of your foreign nationality. For specifics on the procedures for renouncing a foreign nationality, please consult directly with the foreign government or its representatives.

SWEARING TO JAPANESE NATIONALITY
At the nearest city, ward or town office, or at a Japanese Embassy or Consulate abroad, you must state your decision to choose Japanese nationality and abandon your foreign nationality on a special form called the Kokuseki Sentaku Todoke.

Despite these relatively clear guidelines, stories abound of people trying to skirt the restrictions on dual nationality by “hiding” their second citizenship from Japan. Obviously this is not recommended and you should consult an immigration attorney as to the repercussions.

Japan is divided up into 47 regions called prefectures. A prefecture is an administrative unit generally larger than a city or metropolitan region (with the exception of Tokyo).

List of the Prefectures of Japan

“Metropolis” Prefecture:

Tokyo

“Circuit” Prefecture:

Hokkaido

Urban Prefectures:

Osaka
Kyoto

And 43 Other Prefectures (listed below)

Prefectures of Japan

Prefectures by Region:

Hokkaid?

1. Hokkaid?

T?hoku

2. Aomori
3. Iwate
4. Miyagi
5. Akita
6. Yamagata
7. Fukushima

Kant?

8. Ibaraki
9. Tochigi
10. Gunma
11. Saitama
12. Chiba
13. Tokyo
14. Kanagawa

Ch?bu

15. Niigata
16. Toyama
17. Ishikawa
18. Fukui
19. Yamanashi
20. Nagano
21. Gifu
22. Shizuoka
23. Aichi

Kansai

24. Mie
25. Shiga
26. Kyoto
27. Osaka
28. Hy?go
29. Nara
30. Wakayama

Ch?goku

31. Tottori
32. Shimane
33. Okayama
34. Hiroshima
35. Yamaguchi

Shikoku

36. Tokushima
37. Kagawa
38. Ehime
39. K?chi

Ky?sh?

40. Fukuoka
41. Saga
42. Nagasaki
43. Kumamoto
44. ?ita
45. Miyazaki
46. Kagoshima
47. Okinawa