These basic rights and restrictions for public protesters have been shared by the American Civil Liberties Union and other organizations:

Participating in a protest

• On public property: The First Amendment protects free-speech rights on public property, including streets and sidewalks, as long as car and pedestrian traffic is not obstructed.

Civil disobedience — peaceful but unlawful activity as a form of protest — is not protected under the First Amendment. Protesters engaging in such activities can be arrested.

• On private property: Owners can set rules for speech on their property. Police may not restrict protests that are occurring with the consent of the property owner.

Photos and videos

• When you are lawfully present in a public space, you have the right to photograph anything in plain view. Arrests may be recorded on images or video, although the person being arrested must comply with an officer’s orders to stop using a phone or camera during the arrest.

• Be aware that others might be taking your photo while you are at a public protest, and you will have no control over such images and videos that are shared online, the Yale Office of International Students advises.

If you are told to disperse

Police may break up a gathering only if there is a “clear and present danger” of riot, interference with traffic, or other immediate threat to public safety. They must issue a clear dispersal order, including setting a time limit for dispersal, designating exit routes and informing protesters of consequences for failing to leave.

If you are detained

• Don’t argue, resist or obstruct the police, even if you believe your rights are being violated.

• If you are stopped, ask the officer if you are free to leave; if the answer is yes, walk away. If you are detained, ask the officer what crime you are suspected of committing

• You may refuse to show identification, but it’s a good idea to carry it when you’re protesting. If you are detained for an infraction and can show a government-issued ID, the police are required to issue a ticket and — if you sign it — to release you rather than take you to jail. For misdemeanor detention, identification can allow you to be released after fingerprinting and a mugshot photograph.

• You never have to consent to a search of yourself or your belongings, including your phone. The police may pat you down, outside your clothing, if they suspect you have a weapon and may search you after an arrest.

• You do not have to provide your phone password to the police.

• You do not have to say anything or sign anything.

• You have the right to make a local phone call, and if you’re calling your lawyer, police are not allowed to listen.

What police can’t do

• Police cannot treat protesters and counterprotesters differently. They may keep antagonistic groups separated but should allow them to be within sight and sound of one another.

• They may not confiscate a phone or camera or demand to view your photographs or videos without a warrant. They may not delete data.

If you believe your rights were violated

• Write down everything you remember, including the officers’ badge and patrol car numbers.

• Get contact information for witnesses.

• Take photographs of any injuries.

Use this information in filing a written complaint with the agency’s civilian complaint board.

Organizing an event

• You shouldn’t need a permit for small demonstrations — for instance, a small rally in a public park, or a sidewalk march that obeys traffic laws. For larger events that could be seen as “realistically presenting serious traffic, safety, and competing-use concerns,” you may need a permit from the agency that oversees the public space.

• Absent any direct incitement, the organizer of a lawful protest can’t be held responsible for protesters’ unlawful acts or for  counterdemonstrators’ reactions.