## Facts

- Ruben Flores-Villar was born in Tijuana, Mexico, on October 7, 1974, to a U.S.-citizen biological father (age 16 at the time) and a non-U.S.-citizen biological mother.
- Flores-Villar was brought to the United States as an infant for medical treatment and grew up in San Diego with his father and paternal grandmother.
- The father was not listed on the birth certificate but later acknowledged paternity by filing an acknowledgment with the Mexican Civil Registry on June 2, 1985.
- Flores-Villar had prior federal and immigration convictions, including a 1997 marijuana importation conviction and 2003 illegal entry convictions, and he was removed multiple times.
- After being found in the United States following removal, Flores-Villar was charged with illegal reentry under 8 U.S.C. § 1326(a) and (b).
- Flores-Villar claimed he was a U.S. citizen at birth through his father, but the statutory scheme required an unwed citizen father to have 10 years of U.S. physical presence, including 5 years after age 14; his father could not satisfy the post-age-14 requirement because he was only 16 at Flores-Villar’s birth.
- Flores-Villar moved to dismiss the indictment, arguing the citizenship-transmission provisions violated equal protection under the Fifth Amendment due to sex- and age-based classifications.

## Issues

1. Whether former INA provisions imposing different physical-presence requirements on unwed U.S.-citizen fathers than on unwed U.S.-citizen mothers for transmitting citizenship to children born abroad out of wedlock violate equal protection under the Fifth Amendment.
2. Whether requiring an unwed U.S.-citizen father (but not mother) to satisfy a five-year post-age-14 physical-presence component is an unconstitutional age-based classification.

## Decision

- The Ninth Circuit affirmed the district court’s denial of the motion to dismiss and affirmed the conviction under 8 U.S.C. § 1326.
- The court assumed intermediate scrutiny applied to the sex-based claim and rational-basis review applied to the age-based claim, consistent with Supreme Court treatment in analogous citizenship-transmission cases.
- Under those standards, the court held the challenged residence requirements survived constitutional review and rejected Flores-Villar’s equal protection challenge.

## Legal Principles

- Equal protection challenges to federal statutes are analyzed under the equal protection component of the Fifth Amendment’s Due Process Clause.
- Sex-based classifications are reviewed under intermediate scrutiny: the government must show an exceedingly persuasive justification, that the classification serves important governmental objectives, and that it is substantially related to achieving those objectives.
- Age-based classifications are generally reviewed under rational-basis review: the classification need only be rationally related to a legitimate governmental interest.
- In evaluating sex-differentiated citizenship-transmission requirements for out-of-wedlock children born abroad, courts may treat Supreme Court precedent upholding differential treatment of unwed mothers and fathers in the INA framework as controlling where the asserted governmental interests include biological and evidentiary differences and ensuring a sufficient connection between the citizen parent, the child, and the United States.

## Conclusion

The Ninth Circuit upheld the constitutionality of former INA provisions that made it harder for an unwed U.S.-citizen father than an unwed U.S.-citizen mother to transmit citizenship at birth to a child born abroad out of wedlock, concluding the sex-based and age-related residence requirements satisfied intermediate scrutiny and rational-basis review, and it therefore affirmed Flores-Villar’s illegal reentry conviction.


United States v. Flores-Villar, 536 F.3d 990 (9th Cir. 2008)