A more thorough explanation:

The Dombrowski doctrine was a legal rule that allowed individuals to seek a federal-court injunction to prevent prosecution under a state law that violated their First Amendment rights. This rule was established in the case of Dombrowski v. Pfister in 1965.

For example, if a state law was too broad or vague and could potentially infringe on an individual's freedom of speech or religion, they could use the Dombrowski doctrine to seek protection from federal courts.

However, this doctrine was later limited by the Supreme Court in the case of Younger v. Harris in 1971. The Court ruled that federal courts should not intervene in state affairs unless there was a clear and immediate threat to an individual's constitutional rights.

Overall, the Dombrowski doctrine was a short-lived legal rule that aimed to protect individuals from state laws that violated their First Amendment rights, but its scope was later limited by the Supreme Court.