Taiwan's Legislative Yuan Legal Affairs Bureau recently issued a research report on related legal issues concerning the prohibition of marriage between close relatives, suggesting that the competent authority should consider the feasibility of appropriately narrowing the scope of the collateral blood relation marriage prohibition to within the fourth degree of kinship, drawing reference from international legislation in countries like Germany and Japan.
The report notes that the current Civil Code stipulates that marriage between collateral blood relatives within the sixth degree of kinship is null and void. Citing a recent annulment case where a couple was found to be sixth-degree collateral relatives, the Bureau pointed out that declaring a marriage null and void significantly harms the rights of the couple's children, who become non-marital offspring. Therefore, the report suggests reviewing the existing rule and changing the legal consequence for violating the prohibition from "null and void" to "revocable" (meaning the marriage can be annulled upon application by the concerned parties).
Regarding the scope liberalization, the report questions whether the current sixth-degree prohibition is overly broad. While the current regulation was established in 1998 based on eugenic concerns, most modern countries prioritize freedom of marriage, restricting collateral kin marriage generally no further than the third degree. The report argues that in contemporary society, most people do not recognize relatives beyond the fourth degree. Furthermore, given advancements in medical technology, eugenic concerns are no longer a primary justification for the prohibition. The report also highlights a questionable distinction: current law allows same-sex partners who are sixth-degree collateral kin to marry, while prohibiting opposite-sex partners of the same relation (assuming inevitable procreation and eugenic harm).
The proposed amendment, by restricting the prohibition to the fourth degree, would permit marriage among fifth and sixth-degree relatives, such as the children of one's parents' cousins, or one's own cousins' children. However, Chung Chia-pin, Executive Secretary of the Democratic Progressive Party legislative caucus, emphasized that any revision to the Civil Code must be cautious and requires comprehensive discussion. The Taiwan Society of Reproductive Medicine called on the government to focus on improving childcare policies and birth subsidies, rather than viewing consanguineous marriage as the root cause of low birth rates.
