Theories of Liability & Common Defenses

Section 1983 provides a federal cause of action against any person who, acting under color of state law, deprives another of rights secured by the U.S. Constitution or federal law. The plaintiff must establish: (1) deprivation of a constitutional right; (2) by a person acting under color of state law. Section 1983 itself creates no substantive rights — it is a vehicle for vindicating rights guaranteed elsewhere (Fourth Amendment, Fourteenth Amendment, First Amendment, etc.).

Graham v. Connor (1989) 490 U.S. 386 established that excessive force claims against law enforcement are governed by the Fourth Amendment's objective reasonableness standard: whether the use of force was objectively reasonable from the perspective of a reasonable officer on the scene. Relevant factors include the severity of the crime at issue, whether the suspect posed an immediate threat, and whether the suspect was actively resisting or evading arrest.

California's Bane Act provides a state-law civil rights cause of action for interference with constitutional rights by threat, intimidation, or coercion. Unlike § 1983, the Bane Act provides: (1) a $25,000 statutory minimum damages floor per violation; (2) treble damages at the court's discretion; (3) attorney's fees; and (4) no qualified immunity defense — making it the preferred vehicle in California state court civil rights litigation. The Cornell v. City & County of San Francisco (2017) framework controls the intent standard.

Monell v. New York City Dept. of Social Services (1978) 436 U.S. 658 held that municipalities can be sued under § 1983, but only when a constitutional violation results from an official policy, practice, or custom — not merely from a rogue officer's act. A Monell claim requires evidence of: (1) an official policy or widespread practice; (2) deliberate indifference; or (3) a ratification of unconstitutional conduct by a final policymaker.

The Ralph Act provides that all persons have the right to be free from violence or the threat of violence because of their race, color, religion, sex, disability, national origin, sexual orientation, or other listed characteristics. A violation requires proof of violence or threat of violence, motivated (at least in substantial part) by a characteristic listed in the statute. Like the Bane Act, it provides attorneys' fees and civil penalties — making it a valuable companion claim in hate-crime-adjacent civil rights cases.

Substantive due process claims arise when government action shocks the conscience or arbitrarily deprives persons of life, liberty, or property without adequate process. Equal protection claims require proof of discriminatory intent and that similarly situated persons outside the protected class were treated differently. Both claims are cognizable under § 1983 and can be paired with Bane Act claims in California state court.