HOWTO: Use your phone safely at protests
Photo: Bickanski on Pixnio.

HOWTO: Use your phone safely at protests

I’m writing this post as protests and rebellion spread in Minneapolis and across the country after the brutal police killing of George Floyd. The surveillance state – from local police to national agencies – will use every opportunity they can to target activists & those involved in these events.


This article got a bit long. Here’s a TL;DR summary for those rushing out to an event:

  1. Consider if you need your phone at an event. You probably do, but it’s worth thinking about.
  2. Use Signal for communications, and make sure everyone you’re talking with does the same.
  3. Use a strong passcode for your phone and turn off biometrics (fingerprint/face recognition).
  4. Be considerate of who & what you’re taking photos & video of.

Do you need your phone at the event?

As always, answers to security questions depend on your specific situation. Do you not want anyone to know you were at an event? In addition to masking up and not showing any identifying clothing or marks, you may want to leave your phone at home. By the very nature of how cell phone service works, the phone company knows where you are based on what cell towers your phone is connecting to. Google, AT&T and others have been more than willing to give this information to police in the past. While the U.S. Supreme Court ruled in Carpenter v. United States (2018) that law enforcement need to get warrants to get cell phone location information (under what’s known as the third-party doctrine), companies are all too happy to comply with these requests.

Most of us will probably want or need our phones at an event, though: to keep up with the people you came with, to get important safety information, to be aware of emergencies at home, etc. There are still steps to be taken to protect yourself.

Use Signal for messaging

Signal is a secure messaging app – like text messages, Facebook Messenger, WhatsApp, and so on. The difference is Signal’s focus on your privacy.

On your phone, visit in your browser to get a link to download it. Get others in your group/circle to download it as well. Signal only works when everyone is using it.

Regular text messages, also known as SMS, are very insecure. In many cases, once a text is sent from a cell tower to your device, they are unencrypted – meaning that anyone who can intercept the signal can read them. This is particularly important when we consider the use of Stingray technology by police at events. A Stingray is a device that pretends to be a cell tower. Your phone doesn’t know better, so it connects to the Stingray device. From there, the device operator can track the identities of every phone connected and intercept every piece of data sent back and forth – including text messages.

Signal encrypts your messages in such a way that the Signal servers themselves can’t even read them. Only the people in your conversation can read them. Signal doesn’t even save the messages or any information about who you’ve talked to or when you talked.

Securing Signal

Signal is still not a panacea. While it protects you from certain attacks, consider what happens if police get hold of your phone: If they can look at your screen, they’ll see your notifications, which could give them at least a list of people you’re talking to, and so on. If they get into your phone, they see all your past messages.

There are a few settings in Signal that you’ll want to adjust, based on your situation. Open the settings portion of the Signal app for each of these.

Notifications: disable the Contact Joined Signal notification.
Change “Show” to “Name Only” or “No Name or Content”. When you get a notification on your home screen, this will only show either the name of the sender, or just say that you’ve got a new message in Signal.
Doing this is a bit of a hassle, because you have to unlock your phone every time to even see the content of a message. Assess your risk and whether you need to do it.

Privacy: Turn on “Screen Lock” and “Enable Screen Security.” Set “Screen Lock Timeout” to something short, like Instant or 1 minute.
Enable Screen Security prevents Signal from showing previews of your messages when you’re switching between apps.
Screen Lock makes you enter your phone’s passcode to unlock Signal after you haven’t used the app for a minute. It’s a second layer of defense, in case someone grabs your phone while you’re using it. Again, this can create a bit of a hassle, so assess your risk and consider how long you need to set this for.

Your Phone

Finally, a few tips on securing your phone itself.

  1. Use a strong passcode. A 4-digit passcode can be broken by a computer in minutes. I suggest 10+ digits, to increase that timespan to multiple years.
  2. Turn off biometrics. On iPhones, these are known as Face ID or Touch ID – using either facial recognition or your fingerprint to unlock your phone. Because the case law has not been settled and various District Courts disagree, the current situation is generally that police can force you to unlock your phone with your face or finger, but cannot compel you to give them your password. (This is based on a particular reading of 5th Amendment rights against self-incrimination. Technology is fast, and the law is slow.)
  3. Turn off all notification previews: We’ve already addressed how to turn off previews in Signal. But if you get an email, Facebook message or regular text, that preview will still show up.
    On an iPhone, open Settings, then Notifications, then change Show Previews to Never.
    On Android, depending on the version of the software, open Settings, then App & notifications, then Notifications. Turn off “Sensitive notifications” under “Lock screen”

A quick note about photography

If you’re taking photos/videos at an event, please consider the safety of others. A photo taken of someone committing what could be considered an illegal act could also have identifying information of them. Whether your phone is taken and opened by police, or you post the content to social media, you don’t want to be responsible for someone being arrested.

I believe that we will win!

Digital security is just one aspect of being safe during a protest – or rebellion. This article outlined some basic tips and the reasoning behind them.

We need to be aware of the surveillance state and its capabilities, but if we are armed with correct and useful information we do not need to be afraid of it.