A Texas statute denied the use of state funds for the education of illegal alien children. In a class action suit, Ps challenged the constitutionality of the statute, claiming that it allowed local school districts to deny enrollment to illegal aliens. The District Court preliminarily enjoined Ds from denying a free education to members of the plaintiff class. The District Court held that illegal aliens were entitled to the protection of the Equal Protection Clause of the Fourteenth Amendment, and that § 21.031 violated that Clause. The court held that it was unnecessary to decide whether the statute would survive a 'strict scrutiny' analysis because, in any event, the discrimination embodied in the statute was not supported by a rational basis. The Court also concluded that the Texas statute violated the Supremacy Clause. The Court of Appeals upheld the injunction. It held that the District Court had erred in finding the Texas statute preempted by federal law. With respect to equal protection, the Court of Appeals affirmed in all essential respects concluding that § 21.031 was 'constitutionally infirm regardless of whether it was tested using the mere rational basis standard or some more stringent test.' Texas (D) appealed, claiming that the statute was not unduly discriminatory. D gave three reasons justifying the existence of the statute: (1) the intent was to protect the state from an influx of illegal immigrants; (2) illegal aliens impose certain burdens on the school system, and this statute would eliminate these problems; and (3) since these children were less likely to remain in the state after school, it would allow the school to concentrate on those that would benefit the state economically in the future.