Strict scrutiny

Strict scrutiny is the most stringent standard of judicial review used by United States courts. It is part of the hierarchy of standards that courts use to determine which is weightier, a constitutional right or principle or the government's interest against observance of the principle. The lesser standards are rational basis review and exacting or intermediate scrutiny. These standards are used to test statutes and government action at all levels of government within the United States.

The notion of "levels of judicial scrutiny," including strict scrutiny, was introduced in Footnote 4 of the U.S. Supreme Court decision in United States v. Carolene Products Co. (1938), one of a series of decisions testing the constitutionality of New Deal legislation. The first and most notable case in which the Supreme Court applied the strict scrutiny standard and found the government's actions valid was Korematsu v. United States (1944), in which the Court upheld the exclusion of Japanese Americans from designated areas during World War II.

U.S. courts apply the strict scrutiny standard in two contexts: when a fundamental constitutional right is infringed, particularly those found in the Bill of Rights and those the court has deemed a fundamental right protected by the Due Process Clause or "liberty clause" of the 14th Amendment, or when a government action applies to a "suspect classification," such as race or national origin.

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