Levels of Scrutiny
How courts determine if the government is violating the Constitution.
Courts come up with guidelines to help make determinations. When it comes to reviewing whether a government action (often a law or a regulation) violates the Constitution, a court first chooses a Level of Scrutiny.
Determining a Level of Scrutiny
The court must determine whether it will be skeptical of government action, or be less nit-picky. That depends on the sensitivity of the issue. Certain liberties are more highly protected than others. Certain classes of people are more highly protected than others. These factors raise suspicion.
The court will evaluate various factors that are likely to raise suspicion to determine the level of scrutiny.
You can consider the levels of scrutiny as existing on a spectrum: where Rational-Basis Review is at one end and Strict Scrutiny is at the other.
Our infographic outlines the three most common points on the spectrum (Rational-Basis, Intermediate Scrutiny, and Strict Scrutiny). The Supreme Court has found the following situations to correspond to these levels of scrutiny.
The Supreme Court came up with Rational-Basis Review in Nebbia v. New York (1934). The NY government had decided to regulate the prices of dairy (setting a minimum retail price). Nebbia, a store owner, violated the law and challenged that his conviction was unfair. The Due Process Clause in the Constitution, Nebbia said, protected him against unfair or unreasonable regulatory power.
In denying Nebbia of his claim, the Supreme Court said the government has the right to create general restrictions on private conduct for the purpose of regulating the economy, so long as the government action is not "arbitrary, discriminatory, or demonstrably irrelevant" to the action regulated.
This case did not deserve any higher level of scrutiny because it did not involve a particularly sensitive issue, like free speech or discrimination against someone in a protected class. It was, in the Court's opinion, just regular government regulation, and it only had to be reasonable.
Strict Scrutiny is at the opposite end of the spectrum. The Supreme Court has declared government regulation should be scrutinized very strictly when it infringes on a protected liberty (like procreation or marriage) or a protection action (like political speech), or when it unfairly discriminates against a protected class (like race or national origin).
Skinner v. Oklahoma (1942) was an early case in which the Court decided the harshest review (strict scrutiny) was appropriate. Oklahoma had passed a law allowing the state to sterilize a person who was convicted three or more times of a "felony of moral turpitude." The Court said the act, intending to deprive an individual of one of the most basic liberties - "a right which is basic to the perpetuation of a race" - deserved "strict scrutiny." The Court had not yet adopted the formal characterization of the standard that courts use today (reviewing to ensure the law is "narrowly tailored to achieve a compelling government interest").
A well-known case in which the Supreme Court applied Strict Scrutiny and made the rare ruling in favor of the government is Korematsu v. United States (1944). During a state of war with Japan, the U.S. government had issued an Executive Order that all Japanese must be excluded from certain sensitive areas. One of them was San Leandro, California, where Korematsu lived. Of Japanese descent, Korematsu was convicted for refusing to leave. He challenged the law as a violation of his Constitutional liberty rights. The Court admitted that classifications based on race had to satisfy the most "rigid scrutiny" (strict scrutiny) but said the "circumstances of direst emergency and peril" justified the action. Korematsu is known today as an "ugly" mark of our nation's past, but it has never been explicitly overruled. See this article in Politico connecting the case to the case over Trump's Travel Ban. And one in the Washington Post written by Korematsu's daughter.
During the civil rights era and through today, the Supreme Court has applied Strict Scrutiny to government actions that classify people based on race. For example, in Loving v. Virginia (1967), the Supreme Court applied Strict Scrutiny to strike down Virginia's law banning interracial marriage.
Government classifications based on gender deserving a moderate level of scrutiny ("quasi-suspect classifications"). Ironically enough, the standard was created in a case bought by a male against an Oklahoma law allowing females to purchase alcohol at a younger age (18) than it allowed males (21). In Craig v. Boren (1976), the Supreme Court said the law did not withstand "intermediate scrutiny."
Restrictions on certain types of speech that are regarded as less expressive than political speech (like commercial speech) also get intermediate scrutiny. The Supreme Court will be hearing NIFLA v. Becerra this term, a case in which the appeals court applied intermediate scrutiny to a California law requiring anti-abortion clinics to give notice that abortions are available elsewhere. NIFLA will argue to the Supreme Court that the law deserves Strict Scrutiny.
See this report on Levels of Scrutiny Under the Equal Protection Clause from the University of Missouri, Kansas City.