T he existence of a sizable population of "DREAMers" in the United States has prompted questions about unauthorized aliens' eligibility for admission to public institutions of higher education, in-state tuition, and financial aid. The term DREAMer is widely used to describe aliens who were brought to the United States as children and raised here but lack legal immigration status. As children, DREAMers are entitled to public elementary and secondary education as a result of the Supreme Court's 1982 decision in Plyler v. Doe . There, the Court struck down a Texas statute that prohibited the use of state funds to provide elementary and secondary education to children who were not "legally admitted" to the United States because the state distinguished between these children and other children without a "substantial" goal, in violation of the Equal Protection Clause of the Fourteenth Amendment to the U.S. Constitution. The Plyler Court did not, however, purport to address unauthorized aliens' access to higher education, and several states subsequently adopted laws or practices barring their enrollment at public institutions of higher education. Congress has also restricted unauthorized aliens' eligibility for "public benefits," a term which has generally been construed to include in-state tuition and financial aid. Emphasizing DREAMers' ties to the United States, including their attendance at public elementary and secondary schools, some would permit them to remain in the United States legally, or expand their access to higher education. For example, in every Congress from the 109 th to 113 th , Members have introduced, either as separate bills or parts of other measures, versions of the Development, Relief, and Education for Alien Minors (DREAM) Act—from which DREAMers take their name—that would create a pathway to citizenship for them, as well as remove certain restrictions on states' ability to grant in-state tuition to unauthorized aliens. No such legislation has been enacted by Congress to date. However, several states have passed their own DREAM Acts, which permit some DREAMers to receive in-state tuition or, less commonly, state financial aid (but cannot provide a pathway to citizenship because Congress has exclusive power over naturalization). The Obama Administration also began granting deferred action—a type of relief from removal—to qualifying DREAMers in 2012. Because aliens granted deferred action are generally viewed as "lawfully present" for purposes of federal immigration law, they could potentially be deemed eligible for certain educational benefits that are denied to aliens who are "unlawfully present." However, not all aliens commonly known as DREAMers have been granted deferred action, and even those who have been granted deferred action are considered to be lawfully present only while they are in deferred action or other similar status. Others, however, emphasize DREAMers' presence in the United States in violation of federal immigration law, and seek to ensure that public benefits are made available only to U.S. citizens, lawful permanent residents (LPRs), and nonimmigrants with legal status. Several states have, for example, adopted measures barring unauthorized aliens from attending public institutions of higher education. Certain states have also reiterated, or sought to expand upon, existing federal restrictions upon unauthorized aliens' receipt of public benefits in order to ensure that they do not receive in-state tuition or state financial aid. This report surveys key legal issues pertaining to unauthorized alien students' access to higher education, in-state tuition, and financial aid. State measures that would deny or provide access to public institutions of higher education, in-state tuition, and financial aid to unauthorized aliens have been challenged on various grounds. While these grounds can vary depending upon the specific statute or practice in question, the grounds most commonly asserted appear to be violations of the Equal Protection and Supremacy Clauses of the U.S. Constitution. Thus, these provisions are the focus of discussion in this report, and the following paragraphs provide an overview of the basic principles implicated in discussions of equal protection and preemption. The Equal Protection Clause of the Fourteenth Amendment bars states from "deny[ing] to any person within [their] jurisdiction the equal protection of the laws." Aliens have been found to be encompassed by the Fourteenth Amendment's usage of "person." As a result, measures that would treat aliens differently than citizens may be subject to challenge on equal protection grounds. The level of scrutiny applied by the courts in reviewing such measures frequently determines whether the measure is upheld or struck down. With "rational basis review," the challenged measure will generally be upheld if it is a rational means of promoting a legitimate government objective. The measure is "presumed constitutional," and those challenging the law have the burden of negating all possible rational justifications for the classification. In contrast, with "strict scrutiny," the challenged measure will be upheld only if the government can demonstrate that the measure is necessary to achieve a compelling interest and is narrowly tailored for that purpose. Courts have also applied other tests, falling between rational basis review and strict scrutiny, in some cases due to the persons or rights affected by the measure. The level of scrutiny applied to measures that classify on the basis of alienage depends, in part, on whether the measure is federal, or state or local. Because Congress's plenary power over immigration permits it to enact measures as to aliens that would be unconstitutional if applied to citizens, federal classifications based on alienage are subject to rational basis review, and have generally been upheld. For example, in its 1976 decision in Mathews v. Diaz , the Supreme Court upheld a federal law that barred LPRs who had not resided in the United States for five years from enrolling in Medicare Part B, because it viewed the measure as a valid exercise of the federal government's authority to regulate the entry and residence of aliens, not as "irrational." State and local measures, in contrast, have generally been subject to strict scrutiny, unless (1) the restrictions involve "political and governmental functions," or (2) Congress has "by uniform rule prescribed what it believes to be appropriate standards for the treatment of an alien subclass." However, it is important to note that the Supreme Court decisions applying strict scrutiny to state or local measures that treated aliens differently than citizens all involved lawful permanent resident aliens (LPRs), and the Court in Plyler expressly declined to apply strict scrutiny to the Texas statute because "undocumented status is not irrelevant to any proper legislative goal." Instead, the Plyler Court applied a level of scrutiny that has since come to be characterized as "intermediate scrutiny," requiring the state to show that the challenged measure furthered a "substantial" goal. Some have suggested, however, that the heightened level of scrutiny given to the Texas measure in Plyler reflects the facts and circumstances of the case—which involved a law that a majority of the Court viewed as depriving "minor children" of a "basic education"—and is not generally applicable to classifications involving unauthorized aliens. Neither education, nor receipt of public benefits, has been recognized as a fundamental right for purposes of equal protection, such that its denial would result in the application of strict scrutiny. The Plyler Court subjected the denial of access to public elementary and secondary education to intermediate scrutiny. However, as previously noted, this degree of scrutiny may reflect the facts and circumstances of the case. Similarly, receipt of public benefits has generally been seen to fall within the "area of economics and social welfare," and classifications affecting such interests, standing alone (i.e., not involving a suspect classification of persons), are generally subject to rational basis review. The doctrine of preemption, in turn, derives from the Supremacy Clause of the U.S. Constitution, which establishes that federal law, treaties, and the Constitution itself are "the supreme Law of the Land, ... any Thing in the Constitution or Laws of any state to the Contrary notwithstanding." Thus, one essential aspect of the federal structure of government is that states can be precluded from taking actions that would otherwise be within their authority if federal law would be thwarted thereby. Because the Constitution entrusts Congress with the power to regulate immigration, state or local measures that purport to regulate immigration—by determining which aliens may enter or remain in the United States, or the terms of their continued presence—are, per se, preempted, regardless of whether Congress has legislated on the matter. Other measures, which affect aliens, but do not constitute regulation of immigration, could also be found to be preempted, depending upon the scope of any congressional enactments. Specifically, federal statutes may preempt state and local measures in one of three ways: 1. the statute expressly indicates its preemptive intent ( express preemption ); 2. a court concludes that Congress intended to occupy the regulatory field, thereby implicitly precluding state or local action in that area ( field preemption ); or 3. state or local action directly conflicts with or otherwise frustrates the purpose of the federal scheme ( conflict preemption ). State actions in fields that have traditionally been subject to state regulation are sometimes said to be accorded a presumption against preemption whenever Congress legislates in the field. Education has historically been seen as a local, not a federal, matter. However, a presumption against preemption does not appear to have been applied, to date, in any case involving unauthorized aliens' access to higher education, in-state tuition, or financial aid. To the contrary, at least one court has questioned whether a presumption against preemption continues to apply in the immigration context. Two federal statutes are generally noted in discussions of whether state measures regarding unauthorized aliens' access to public higher education, in-state tuition, and state financial aid are preempted.