Smartphone Encryption and the Law: Can Police Make You Unlock Your Phone?

Last reviewed: October 12, 2026. This article is general information, not legal advice. The law on forced phone unlocking is unsettled and differs between courts and states; if you are facing a search, an order or charges, speak to a criminal defense lawyer.

Your phone probably holds more about your life than any filing cabinet ever did, and the encryption built into it is what keeps strangers out. If you're wondering how the law around smartphone encryption actually works, the honest answer is that it rests on two old constitutional rights, applied to a very new kind of device, and courts don't always agree on the details.

Short answer: Encrypting your own phone is legal. Police generally need a warrant to search a phone's contents, under Riley v. California (2014). Whether the government can force you to unlock it, with a passcode or with your face or fingerprint, depends on the court: judges are split, and the US Supreme Court hasn't decided the issue. At the US border, the rules are looser.

Two different questions: searching the phone and unlocking it

It helps to separate two things that often get blurred together.

1. May the government look inside your phone? That is a Fourth Amendment question about searches and warrants.
2. May the government make you open it? That is a Fifth Amendment question about being forced to incriminate yourself.

A warrant answers the first question. It doesn't automatically answer the second. Police can have a valid warrant to search a phone and still be unable to get in because it's encrypted, which is exactly why the unlocking cases exist.

The warrant rule from Riley v. California

Before 2014, police could often search items found on someone they arrested. In Riley, the Supreme Court refused to stretch that rule to phones. The Court held that police generally may not, without a warrant, search digital information on a cell phone seized from a person who has been arrested.

The decision left room for real emergencies. The Court noted that the exigent circumstances exception could still justify an immediate search in some situations, giving examples such as a suspect texting an accomplice about a bomb or a child abductor with information about the child's location on the phone.

Riley has limits. In United States v. Payne (2024), for example, the Ninth Circuit held that Riley did not apply to a search of a California parolee's phone under his parole search conditions.

Can you be forced to give up your passcode?

The Fifth Amendment protects you from being compelled to be a witness against yourself. Courts ask whether forcing you to unlock a phone is "testimonial", meaning it communicates something from your own mind. There's also a judge-made exception called the foregone conclusion doctrine, which comes from Fisher v. United States (1976): if the government already knows the facts your act would reveal, the act may not be protected.

State high courts have reached different results on passcodes:

• Pennsylvania. In Commonwealth v. Davis (2019), the Pennsylvania Supreme Court held that compelling a defendant to reveal his computer password was testimonial and privileged under the Fifth Amendment, and that the foregone conclusion exception could not apply to it.
• Indiana. In Seo v. State (2020), the Indiana Supreme Court reversed a contempt order against a woman who refused to unlock her iPhone, holding that forcing her to unlock it would violate her Fifth Amendment rights.
• New Jersey. In State v. Andrews (2020), the New Jersey Supreme Court went the other way. It agreed that producing a passcode is testimonial, but held that the foregone conclusion exception applied on that record, so the defendant could be ordered to disclose his passcodes. The US Supreme Court declined to review the case in May 2021.

So the same request could be treated differently depending on the state and the facts.

Face ID and fingerprints: courts are split

Biometric unlocking adds another twist. Some courts say pressing a thumb to a phone is like giving a fingerprint at booking: a physical act, not testimony. Others say unlocking a phone, however it's done, tells the government that you control the device.

• Ninth Circuit. In United States v. Payne (2024), the court held that officers forcing a parolee's thumb onto his phone was not testimonial, because it required no "cognitive exertion", so the Fifth Amendment did not apply.
• D.C. Circuit. In United States v. Brown (2025), the court held that law enforcement violated the Fifth Amendment when the FBI directed a defendant to unlock his phone with his thumb, because doing so revealed his knowledge of how to open it and his control over it.
• State courts. The Payne opinion itself noted that state courts are "equally split", citing an Oregon decision treating biometric unlocking as testimonial and a Minnesota decision treating it as non-testimonial.

Because of this split, a passcode and a fingerprint may not get the same protection, and the answer may change if the Supreme Court eventually takes up the question.

Phone searches at the US border

The border is a special zone where the government has broader search powers. US Customs and Border Protection (CBP) explains its policy this way:

• A basic search is an officer reviewing the device manually, without external equipment.
• An advanced search means connecting equipment to copy or analyze the device. Under CBP policy, it requires reasonable suspicion of a violation of law CBP enforces, or a national security concern, plus approval from a senior manager.
• If a device can't be inspected because it's protected by a passcode or encryption, CBP says it may be detained or subject to other action.
• Officers are to disable network connections and not use your device to access information stored only remotely (in the cloud).

CBP reports that it searched the devices of 55,318 international travelers in fiscal year 2025, out of more than 419 million travelers processed.

Courts have added their own limits in some areas. In United States v. Cano (2019), the Ninth Circuit held that manual phone searches at the border may be done without reasonable suspicion, but forensic searches require reasonable suspicion that the phone contains digital contraband.

What about export controls on encryption?

Encryption is also regulated as a technology for export purposes. The Commerce Department's Bureau of Industry and Security (BIS) explains that encryption items fall under Category 5, Part 2 of the Export Administration Regulations, and that most encryption products can be exported to most destinations under "License Exception ENC" once the exporter meets the classification and reporting requirements. These rules are aimed mainly at companies that make and ship encryption products. If your business develops apps or devices that use cryptography, check the BIS guidance.

Practical points if police want into your phone

• A request is not a court order. Police may ask you to unlock your phone. Whether you agree is a decision best made with a lawyer, especially if you're a suspect. Consent can make a search lawful without a warrant.
• A court order is different. If a judge orders you to unlock a device, refusing can carry consequences, as the contempt order in Seo shows. Talk to a lawyer before deciding what to do.
• Don't destroy or hide data. Deleting evidence after you know about an investigation can create separate criminal problems.
• Travel thoughtfully. If you're crossing the border with sensitive work or client data, consider what you really need on the device and check your employer's policy.
• Know your local rule. Because state and federal courts disagree, the answer where you live may differ from a headline about another state.

If you're dealing with a criminal case more generally, our guides on the burden of proof in a criminal case and who the plaintiff is in a criminal case explain the basics.

Sources

• Fourth Amendment: Cornell LII
• Fifth Amendment: Cornell LII
• Riley v. California (2014): Cornell LII
• Fisher v. United States (1976): Cornell LII
• United States v. Payne, 99 F.4th 495 (9th Cir. 2024): Ninth Circuit opinion (PDF)
• United States v. Brown, No. 23-3074 (D.C. Cir. Jan. 17, 2025): D.C. Circuit opinion (PDF)
• State v. Andrews (N.J. 2020): CourtListener and the US Supreme Court docket, No. 20-937
• Commonwealth v. Davis (Pa. 2019): CourtListener
• Seo v. State (Ind. 2020): CourtListener
• United States v. Cano (9th Cir. 2019): Ninth Circuit opinion (PDF)
• CBP, Border Search of Electronic Devices: cbp.gov
• Bureau of Industry and Security, Encryption controls: bis.gov