Writing for the Court, Justice Byron White rejected the Fifth Circuit’s conclusion that the mentally disabled constitute a quasi-suspect class deserving heightened scrutiny. Justice White emphasized that intellectual disabilities are relevant to many areas of legislative concern, so legislatures must retain the flexibility to design laws and policies addressing their needs. He explained that intellectual disabilities vary widely in severity, and legislative measures for accommodations or supervision are often legitimate. Furthermore, Justice White pointed to action taken by federal and state governments in passing the Rehabilitation Act of 1973 and the Education of the Handicapped Act, demonstrating political responsiveness to the needs of the disables and undermining any claim that they’re “politically powerless”. He explained that unlike race or alienage, classifications based on disability are not “so seldom relevant to the achievement of any legitimate state interest that laws grounded in such considerations are deemed to reflect prejudice.” On this line of reasoning, the Court determined that rational basis review was appropriate.

Even under a rational basis review, the Court struck down the ordinance as applied to CLC’s group home, finding no rational basis for treating the group home differently from other permitted uses in the R-3 zoning district, including fraternity houses, boarding houses, nursing homes, and apartment complexes. The Court contended that the proximity to the junior high school was invalid since many disabled students already attended the school, and concern over floods was irrelevant since other institutions allowed under the ordinance could also locate on flood plains. Regarding density, the Court noted that nothing in the ordinance prevented larger groups of non-disabled persons from living together in the same area. The Court found that mere negative attitudes or fears of neighbors “are not permissible bases” for government decision-making.

Ultimately, the Court concluded that the denial of the permit “appears to rest on an irrational prejudice against the mentally retarded” and therefore violated the Equal Protection Clause of the Fourteenth Amendment. The Court affirmed the Fifth Circuit as to the ordinance’s invalidity as applied but vacated the ruling that intellectual disability constituted a quasi-suspect classification.