Government regulation of speech on its own property is analyzed by classifying the property.

Traditional public forums — streets, sidewalks, parks — have by long tradition been devoted to assembly and debate. Content-based restrictions face strict scrutiny. Content-neutral time, place and manner restrictions are permitted if narrowly tailored to a significant government interest and leaving ample alternative channels.

Designated public forums are created when government intentionally opens property for expressive use. While open, the same standards apply as in a traditional forum.

Limited public forums are opened for particular subjects or speakers. Restrictions must be reasonable in light of the forum’s purpose and viewpoint neutral. This is the category into which most municipal meeting public comment periods fall.

Non-public forums are government property not opened for expression, where reasonable, viewpoint-neutral restrictions suffice.

Government speech is not a forum at all, and the government may say what it chooses. The boundary between government speech and a forum for private speech is heavily litigated in monuments, plaques and specialty plates.

Practical municipal application. Public comment rules limiting time, requiring germaneness and prohibiting disruption are generally sustainable. Rules excluding criticism of officials, or removing a speaker for tone, are where liability arises.