## Facts

- Martin Richard Israel and Tammy Lee Bannon Israel became brother and sister solely by adoption after Martin’s father married Tammy’s mother and later adopted Tammy.
- Martin and Tammy were not related by half or whole blood.
- The couple applied for a Colorado marriage license.
- Norman C. Allen, the Jefferson County Clerk and Recorder, denied the application under a statute prohibiting marriage between a brother and sister “by the half or the whole blood or by adoption.”
- The couple sought declaratory relief challenging the adoption-based prohibition as unconstitutional.
- The district court held that the adoption-based prohibition violated equal protection, severed the words “or by adoption,” and invalidated the denial of the license.
- The clerk appealed directly to the Colorado Supreme Court.

## Issues

1. Whether Colorado’s statutory ban on marriage between siblings “by adoption,” as applied to adopted siblings not related by blood, violates equal protection.
2. Whether the unconstitutional portion of the statute could be severed while leaving the remaining incest prohibitions intact.

## Decision

- The Colorado Supreme Court affirmed the judgment invalidating the adoption-based prohibition.
- The court held the “or by adoption” portion of the sibling-marriage prohibition unconstitutional as a denial of equal protection.
- The court applied rational-basis review, concluding the provision failed even “minimum rationality” and declined to decide whether marriage is a fundamental right requiring strict scrutiny.
- The court approved severance of the words “or by adoption,” leaving intact prohibitions on marriage between ancestors and descendants and between siblings related by half or whole blood.

## Legal Principles

- A marital restriction that classifies persons in a way that does not rationally relate to legitimate state interests violates equal protection even under rational-basis review.
- Traditional justifications for incest prohibitions (e.g., genetic risks and protection of family structure) do not rationally support barring marriage between siblings who are related only by adoption and have no blood relationship, absent a logical fit to those interests.
- A court may sever unconstitutional statutory language when the remaining provisions are complete, workable, and consistent with the legislative scheme.

## Conclusion

Colorado’s prohibition on marriage between siblings “by adoption” was unconstitutional as applied to adopted siblings who were unrelated by blood because it lacked a rational relationship to asserted state interests; the invalid language was severed, and the remainder of the incest-marriage statute remained enforceable.


Israel v. Allen, 195 Colo. 263, 577 P.2d 762 (Colo. 1978)