On Monday, People For the American Way Foundation signed on to an amicus brief urging the Supreme Court to reverse the Ninth Circuit’s decision to enforce a section of the Immigration and Nationality Act that imposes a greater residency requirement for unmarried citizen fathers to transfer citizenship to their children born abroad than on unmarried citizen mothers.

The statute permits unmarried citizen fathers to transmit citizenship only if they have lived in the U.S. prior to the child’s birth for ten years, five of them after the age of 14. Mothers, on the other hand, are only required to have lived in the U.S. for just one year prior to the child’s birth. The petitioner’s father was 16 when his son was born, making it impossible for him to meet the requirement of five years of residency after age 14. Mr. Flores-Villar filed suit on the grounds that the law violates the equal protection component of the Fifth Amendment’s due process clause.

PFAWF’s brief, authored by the National Womens’ Law Center, argues that such gender-based discrimination perpetuates the old stereotype that unwed fathers have less meaningful relationships with their children than do unwed mothers, and the Supreme Court has rejected the use of such stereotypes in justifying gender-based classifications. The classifications also do nothing to further the government’s stated objective of encouraging parent-child relationships, and in countries where citizenship is derived from the father, would render stateless the children of fathers who cannot meet the requirements.

If the Supreme Court were to uphold the Ninth Circuit’s decision, it would be ignoring over 30 years of Equal Protection jurisprudence to enforce a discriminatory law that perpetuates outdated stereotypes and is harmful to family relationships.