Strict scrutiny is a form of judicial review that courts use to determine the constitutionality of certain laws. To pass strict scrutiny, the legislature must have passed the law to further a "compelling governmental interest," and must have narrowly tailored the law to achieve that interest. A famous quip asserts that strict scrutiny is "strict in name, but fatal in practice."
For a court to apply strict scrutiny, the legislature must either have significantly abridged a fundamental right with the law's enactment or have passed a law that involves a suspect classification. Suspect classifications have come to include race, national origin, religion, alienage, and poverty.
Compare to intermediate scrutiny and rational basis.