Equal protection is the legal principle that federal and state governments must provide people with equal protection under the law—meaning the government must treat individuals in the same or similar circumstances equally or the same with respect to rights and protections provided by law. The Due Process Clause of the Fifth Amendment to the United States Constitution requires the United States government to provide equal protection of its laws—and the Fourteenth Amendment’s Equal Protection Clause requires state governments to provide equal protection of their laws.

If a person believes the federal government or a state government has violated the person’s right to equal protection of the laws (based on the government’s enactment of a statute or other action), the person may file a lawsuit against the federal or state governmental entity. A person filing such a claim must prove the governmental entity discriminated against the person and that the discrimination caused actual harm.

The court will analyze the government’s behavior that resulted in the alleged discrimination using one of three legal tests (standards of judicial review): strict scrutiny, intermediate scrutiny, or rational basis scrutiny (also called rational basis review or rational basis test). The appropriate test for reviewing the constitutionality of a statute or other government action is determined by analyzing the nature of the Constitutional right implicated and the nature of the government’s interest or objective in enforcing the statute or other government action.

In California, as in all states, the principle of equal protection is enshrined in both the federal and state constitutions. The Fourteenth Amendment to the U.S. Constitution mandates that no state shall deny any person within its jurisdiction the equal protection of the laws. This means that California must not discriminate against individuals or treat them differently under similar circumstances with respect to rights and protections provided by law. If an individual believes that the state government has violated their right to equal protection, they may file a lawsuit against the state. To succeed, the plaintiff must demonstrate that the state discriminated against them and that this discrimination resulted in actual harm. Courts will evaluate the state's actions using one of three standards of judicial review: strict scrutiny for laws affecting fundamental rights or certain protected classes; intermediate scrutiny for laws involving gender or legitimacy; and rational basis review for all other cases. The level of scrutiny applied depends on the nature of the right affected and the government's interest in the challenged action.