First Amendment litigation almost always opens with a threshold question the merits never reach without first clearing: was the defendant a government actor, since the Amendment restrains state action, not private conduct. Once that gate is cleared, retaliation claims -- typically brought by public employees, contractors, or private citizens against government officials -- require the plaintiff to show engagement in protected speech or activity, an adverse action, and a causal connection between the two, with the burden then shifting to the defendant to show the same action would have occurred regardless of the protected activity. Public employee speech carries an extra layer: courts ask whether the employee spoke as a citizen on a matter of public concern, and if so, balance the employee's speech interest against the government's interest in efficient operations.

A separate track challenges government restrictions on speech directly, and here the level of judicial scrutiny effectively decides the case before the facts are even weighed. A content-based restriction -- one that turns on what is said -- draws strict scrutiny, requiring the government to show a compelling interest achieved through the least restrictive means, a standard restrictions rarely survive. A content-neutral restriction, such as a generally applicable time-place-manner rule, draws only intermediate scrutiny, requiring a significant government interest, narrow tailoring, and ample alternative channels for the speech. Where speech occurs also matters: traditional public forums like streets and parks receive the strongest protection, while non-public or limited forums allow the government considerably more latitude to restrict speech by content or speaker.

The state-action requirement and the scrutiny classification function as gating decisions that shape the entire case before any balancing occurs: a claim against a private actor generally cannot proceed at all, and a restriction correctly classified as content-based rarely survives strict scrutiny, while a content-neutral rule usually survives intermediate scrutiny if the government can show it left reasonable alternatives. In damages claims against individual officials, qualified immunity is a separate and often decisive defense, requiring the plaintiff to show the official violated a clearly established right, which frequently narrows litigation toward injunctive and declaratory relief rather than money damages.