[4] It is the responsibility of the United States Supreme Court in that case to exercise the power of judicial review: the ability to invalidate a statute for violating a provision of the Constitution.
He noted that state legislatures were invested with all powers not specifically defined in the Constitution, but also said that having the federal government subservient to various state constitutions would be an inversion of the principles of government, concluding that if supremacy were not established "it would have seen the authority of the whole society everywhere subordinate to the authority of the parts; it would have seen a monster, in which the head was under the direction of the members".
78 that, "There is no position which depends on clearer principles, than that every act of a delegated authority, contrary to the tenor of the commission under which it is exercised, is void.
[18] Chy Lung v. Freeman was brought to court when a passenger arriving in California on the Chinese vessel "Japan" was detained by the Commissioner of Immigration on the charge of being included by a state statute in the caste of "lewd and debauched women," which require separate bonds from the owner of the vessel they came on in order to land on California's coast.
The Supreme Court ruled against the plaintiff's detention on the basis that the statute preempted the federal legislation's ability to regulate the "admission of citizens and subjects of foreign nations to our shores".
[19] LULAC v. Wilson was brought to the Supreme Court in order to determine the constitutionality of California's Proposition 187, which the League of United Latin American Citizens argued was preempted by the federal government's authority over the regulation of foreign nationals in America.
Proposition 187 was meant to assist cooperative efforts undertaken by national and sub-national governments to place stricter restrictions on undocumented immigrants "from receiving benefits or public services in the State of California".
The Court decided that only a small portion of Proposition 187 was not preempted by the Personal Responsibility and Work Opportunity Reconciliation Act of 1996.
[22] Under the Supremacy Clause, treaties and federal statutes are regarded equally as "supreme law of the land" with "no superior efficacy ... given to either over the other".
Treaties are likewise subject to judicial interpretation and review just as any federal statute, and courts have consistently recognized them as legally binding under the Constitution.
The U.S. Supreme Court applied the Supremacy Clause for the first time in the 1796 case, Ware v. Hylton, ruling that a treaty superseded conflicting state law.
It is, consequently, to be regarded in courts of justice as equivalent to an act of the legislature, whenever it operates of itself, without the aid of any legislative provision.
However, Missouri's potentially broad interpretation was circumscribed in the 1957 case, Reid v. Covert, when the Supreme Court held that treaties and the laws made pursuant to them must comply with the Constitution.
[26] Law scholars called the ruling "an invisible constitutional change" that departed from both longtime historical practice and the plain language of the Supremacy Clause.
The Supreme Court relied on the Supremacy Clause to hold that the federal law controlled and could not be nullified by state statutes or officials.
Any appeal to claims about "national policy", the Court said, were insufficient to overturn a state law under the Supremacy Clause unless "the nature of the regulated subject matter permits no other conclusion, or that the Congress has unmistakably so ordained".
[29] However, in the case of California v. ARC America Corp., 490 U.S. 93 (1989), the Supreme Court held that if Congress expressly intended to act in an area, this would trigger the enforcement of the Supremacy Clause, and hence nullify the state action.