I didn't realize this guide was needed until I saw it.

Keep control of your phone. You may wish to keep the phone on you at all times, or hand it over to a trusted friend if you are engaging in action that you think might lead to your arrest. In any case, you can set the lock screen to turn on quickly, so that if you do lose control of your phone, nobody else gets access easily.

Take pictures and video of the scene. As the ACLU says in a recent Know Your Rights guide, "Taking photographs of things that are plainly visible from public spaces is a constitutional right." Unfortunately, that doesn't stop law enforcement officers from occasionally demanding that protesters stop doing exactly that.

If you're planning to document the protest, you should read the whole guide ahead of time. There are special considerations for videotaping, too, so make sure to brush up on that if you plan to be recording video.

Finally, you may wish to explore options that upload directly to another server. Livestreaming sites, and even social media services, can make sure photos and videos get online before law enforcement officers have a chance to delete them.

Help, I'm being arrested!

You have a right to remain silent—about your phone and anything else. If questioned by police, you can politely but firmly decline to answer and ask to speak to your attorney.

If the police ask to see your phone, tell them you do not consent to the search of your device. Again,since the Supreme Court's decision in Riley, there is little question that officers need a warrant to access the contents of your phone incident to arrest, though they may be able to seize the phone and get a warrant later.

As we said in the last guide, if the police ask for the password to your electronic device you can politely refuse to provide it and ask to speak to your lawyer. Every arrest situation is different, and you will need an attorney to help you sort through your particular circumstance. Note that just because the police cannot compel you to give up your password, that doesn’t mean that they can’t pressure you. The police may detain you and you may go to jail rather than being immediately released if they think you’re refusing to be cooperative. You will need to decide whether to comply.