Case 1: Kabuki stars are different.

Last month, the 38-year-old kabuki actor Kataoka Ainosuke held a press conference and admitted that he is the father of a boy who is now a fifth-year elementary school student. Ainosuke is not married to the boy’s 43-year-old mother, and has not formally “acknowledged” (ninchi) the boy in his family register. Even if he did, the boy would still be indicated as “illegitimate” (hichakushutsu) since the actor has never been married to the woman.

This “hidden child” was revealed by the weekly women’s magazine Josei Seven, though it’s assumed that show biz reporters have known about him for years. The reason they decided to make the relationship public now is because Ainosuke is suddenly a star, owing to his high-profile stint as the replacement for Ichikawa Ebizo, who had to drop out of his New Year’s performances in Kyoto after being injured in a bar brawl in November. Josei Seven says that Ainosuke kept his son a secret because when the boy was born, the actor, who is not from a traditional kabuki family, was still making his name and the notoriety might have ruined his career.

Such notoriety is not damaging to a star from a prestigious kabuki family. Ebizo also fathered a child out of wedlock when he was younger and admitted to it, as did another kabuki prince, Ichikawa Somegoro. Both actors legally acknowledged their issues but neither married the respective mothers. Eventually, they wed different women from more “respectable” backgrounds. The same week Ainosuke confessed to having a son, it was revealed that Ebizo’s wife is several months pregnant with their first child.

The United Nations has for years complained about the “legitimacy” indication in Japan’s family register (koseki). The Japanese government says that the indication helps preserve the unity of families by distinguishing the rights of legitimate heirs from those of illegitimate heirs. In kabuki, however, the distinction is less important. Reporters asked Ainosuke if he was going to cultivate his newly revealed son as a kabuki scion. He said it depended on the boy, but if he did he would have to start training him in the appropriate stage arts as soon as possible. It might also be a good idea to teach him about contraception.

Case 2: Transgenders are different.

On Feb. 26, the Japan Society of Obstetrics and Gynecology said it would offer artificial insemination by donor (AID) to legally married couples whose male half has undergone sex reassignment surgery due to a gender identity disorder and whose gender designation has been changed in his family register. The JSOG previously withheld AID treatment for transgender couples because the Ministry of Justice does not recognize their offspring as being legitimate, and the JSOG did not want to be party to creating illegitimate children.

The JSOG’s reasoning for the new policy is that since it provides AID therapy to any married couple, it would be unethical to deny it to married transgenders. The ministry’s reasoning for denying the legitimacy of an AID child of a transgender couple is that the sperm used to impregnate the wife obviously could not have come from the husband if he was born a woman, even if he’d undergone a sex change. “It’s clear that there is no genetic relationship between father and child,” a ministry spokesperson said.

But the family register doesn’t care about genetics. The ministry does not require non-transgender couples who receive AID therapy to prove that the sperm they used is the husband’s. The only thing that matters with regard to legitimacy in the koseki is that the nominal father and mother of the child are married, and the JSOG adheres to that precept. It only provides AID therapy to married couples, not to single women or unmarried couples.

The ministry says that the purpose of the legitimacy indication is to protect families. In Japan, transgender individuals can legally marry, but even if they do the relevant authorities deem that their children can be illegitimate. In the West, if illegitimacy is seen as a bad thing, it’s usually because two parents are considered better for the well-being of a child than one. Here, illegitimacy is purely an arbitrary designation governed by bureaucratic whim.

Case 3: Politicians are different.

In January, Diet member Seiko Noda gave birth to a boy, the product of a third-party egg that was fertilized with her partner’s sperm and implanted in her uterus. Because Noda had been trying for years to become pregnant and had even written a book about it, her situation — including the fact that she is not “genetically” related to the baby — is public knowledge.

As far as the Ministry of Justice is concerned, this lack of genetic connection was not a problem because Noda actually gave birth to the child. The problem was that she and her partner were not married, so after the delivery but before Noda’s partner brought the birth report to the authorities, he and Noda registered their marriage so that the child would be “legitimate.” The couple had not married before because Noda wanted to retain her surname and in Japan married couples are required by law to choose one name between them. In this case, the husband took his wife’s name.

Noda is in favor of bessei, or allowing separate names for husbands and wives, an idea conservatives abhor because, like illegitimacy, they believe it undermines the family. But Noda’s reasoning is not fundamentally at odds with that viewpoint. On her website, she says there are two kinds of people who support bessei: Those, like her, who want to keep their family name so that they can pass it on; and those who are reflexively antiauthority, a group that, Noda implies, operate out of selfish impulses. In other words, you should have the right to keep your birth name as long as your intentions are proper.

Philip Brasor blogs at philipbrasor.com.