Since President Trump was inaugurated just a few months ago, there have been a number of dramatic changes to U.S. immigration policy.

One shift is happening at the borders, where CBP appears to be taking a more aggressive approach with those seeking admission to the United States. You may have seen the alarming reports of individuals being refused entry to the U.S.—or even detained—or heard about folks being turned away for having private messages critical of President Trump on their phone.

Of course, we don’t always know the full story with these incidents, but it seems clear: all travellers to the U.S. should be prepared for heightened scrutiny at the border.

We know that this all sounds a little scary, especially if you’re planning to interact with CBP anytime soon. So here’s a quick guide on the laws of phone security at the border—it’s important to know your rights!

So, can the U.S. authorities search my phone at the border?

The short answer is: yes.

The long answer is a bit more complicated. Let’s dive in.

The border search exception to the Fourth Amendment

The Fourth Amendment to the U.S. Constitution protects individuals against “unreasonable searches and seizures.” Under normal circumstances, this means that law enforcement generally must obtain a warrant—approved by a judge—based on probable cause to believe that evidence of a crime will be found before they can search your belongings.

But the border is different.

Thanks to the “border search exception”– a legal carve-out affirmed by the U.S. Supreme Court – federal officers may generally conduct routine, warrantless searches of persons and items entering the United States without probable cause, or even reasonable suspicion, of unlawful activity.

This means CBP can search the devices of foreign travellers seeking admission to the United States. Airports, seaports, and land crossings all count.

What if I say no?

If you state that you don’t consent to a search, what happens next will partly be determined by your legal status:

• U.S. Citizens can’t be refused entry, but officials can detain you, interrogate you, and potentially seize your devices for deeper forensic examination.
• Green Card holders face similar treatment—but with the added risk of being flagged for an immigration hearing.
• Foreign nationals have the least protection. You can simply be denied entry and put on a plane home.

How can I protect my data when traveling to the U.S.?

Given all of the above, you may want to consider taking some precautions if you’re thinking of hopping on a plane in the near future. At very least, you should understand the potential consequences of refusing a device search, whic based on your immigration status.

Beyond that, we think the following advice from ACLU is on point:

• Travel with as little data and as few devices as possible. The less you’re carrying, the less there is to search. Consider using a travel-only smartphone or laptop that doesn’t contain private or sensitive information. You could also ship your devices to yourself in advance. (Be aware that CBP claims the authority to search international packages so it is best to encrypt any devices that you ship.) Keep in mind that a forensic search of your device will unearth deleted items, metadata, and other files.
• Encrypt devices with strong and unique passwords and shut them down when crossing the border. A good resource on how to do so can be found here.
• Store sensitive data in a secure cloud-storage account. Disable any apps that connect to cloud-based accounts where you store sensitive communications or files, and don’t keep a copy of cloud-stored data in your physical possession. In July 2017, CBP publicly stated it is against policy for border agents to search cloud-stored data on electronic devices. This means that any search of an electronic device at the border should not extend to data that is only accessible via the internet — such as email or social media messages and posts that are stored on remote servers. Keep in mind that if there are copies of cloud-stored data cached on the device (for example, recent emails), border agents will be able to see that information.
• Upload sensitive photos on your camera to your password-protected laptop or a cloud-storage account. Digital cameras don’t offer encrypted storage, so you should consider backing up your photos and deleting them from your camera and reformatting the camera’s memory card.
• Turn on airplane mode for all of your electronic devices before crossing a border checkpoint. CBP stated in July 2017 that its policy does not permit searches of cloud-stored data that is accessible from electronic devices through the internet. Keeping your devices in airplane mode will help ensure compliance with this policy.
• Let officers know if you have privileged material on your device. The 2018 CBP Directive on border device searches requires certain procedures to be followed before border officers can search attorney-client or attorney work product materials. If you have any privileged or sensitive material on your device, tell the border officers before they begin any search.

How does this compare to the UK?

You may or may not be surprised to learn that the UK has somewhat similar search powers – though they’re grounded in different laws.

Under Schedule 7 of the Terrorism Act 2000, border officers can stop, question, and detain individuals without suspicion for up to six hours. They can also seize your phone or laptop and require you to provide passwords. Refusal is a criminal offence, and yes, people have been prosecuted for not handing over their passwords.

However, UK law has faced legal challenges, so while the UK still maintains broad authority at the border, pressure is mounting to increase oversight and accountability.

The long and short of it?

There’s no question: visitors should expect greater scrutiny at the U.S. border.

Even if it’s ultimately pretty unlikely that CBP will search your device(s), you need to know they have the right do so if they wish—and, if you’re not a U.S. citizen or permanent resident, refusal to comply may end your American Dream before it has even begun. So if you’re traveling with sensitive data, it’s worth considering what’s on your devices and how best to protect that information.

The Electronic Frontier Foundation has additional details for those who wish to do a deeper dive.

Travel safe.