Common legitimate interests include traffic flow, residential quiet, safe access to buildings, and avoiding two large events at the same place and time. The rule need not be the least restrictive imaginable, but it cannot burden substantially more expression than necessary to address the asserted interest.

Content neutrality concerns the government's justification. A sound limit on amplified volume applies regardless of whether the speaker supports the mayor, opposes a war, advertises a concert, or preaches a religion. A rule banning only labor picketing or charging more when officials expect hostile listeners is not neutral in the same way. Government may not make protected speech more expensive because opponents might react violently; that would reward a heckler's veto.

Permit systems need objective standards, definite time limits, and reviewable decisions. Criteria such as route capacity and scheduling conflicts can guide an administrator. Authority to deny a permit whenever a demonstration is "not in the public interest" invites viewpoint discrimination and can operate as an invalid prior restraint.

Forum classification comes before the test. In a designated public forum that government has intentionally opened for broad expression, rules generally resemble those for a traditional forum. A limited forum may be confined to certain subjects or speakers, but exclusions within its boundaries must remain viewpoint neutral. In a nonpublic forum, such as an internal agency mail system, government may impose reasonable, viewpoint-neutral limits compatible with the property's purpose.

Government ownership alone does not make every location a public forum. A sidewalk and a secure operations room are both public property but serve different functions.

A city requires all amplified park events to end at 10 p.m., applies the limit evenly, and leaves daytime events and unamplified communication available. The rule addresses noise, is tailored to a significant interest, and leaves realistic alternatives. If the city waives the rule for speakers who praise local policy but enforces it against critics, the practice becomes viewpoint discriminatory despite neutral wording.

Use the five-step method: identify the official restriction, the expression, the forum, the government's actual reason, and the public-forum test. A rule is not a prior restraint merely because a permit is required, nor is it valid merely because officials call it a scheduling measure. Standards, neutrality, tailoring, and alternatives determine the result.

Video lesson: Freedom of Speech: Crash Course Government and Politics #25