Can Police Compel You to Unlock Your Phone? Pennsylvania’s Rule (and What Other Courts Are Doing in 2025)

Short answer for Pennsylvania: Police cannot force you to reveal or speak your passcode/password. That’s protected by the Fifth Amendment under the Pennsylvania Supreme Court’s decision in Commonwealth v. Davis (2019).¹

Biometrics (fingerprint/Face ID): Pennsylvania’s appellate courts haven’t squarely decided this yet. Elsewhere, courts disagree—some allow compelled fingerprint/face unlock, others say it violates the Fifth Amendment. As of October 23, 2025, there’s an emerging split between federal appeals courts, making this a live issue to watch.^7–10

The two buckets: passcodes vs. biometrics

Passcodes/passwords (what you know)

Pennsylvania’s high court held that compelling a password is “testimonial” and violates the Fifth Amendment. The Court rejected the government’s “foregone conclusion” argument for passwords—because forcing you to reveal the contents of your mind is exactly what the privilege forbids. Result: no compelled disclosure of a passcode in PA.¹

Outside Pennsylvania, outcomes vary: some courts (e.g., Indiana) likewise prohibit compelled passcodes, while others (e.g., New Jersey) allow compelled disclosure under the foregone‑conclusion doctrine. ^{5, 6}

Biometrics (what you are)

Many courts treat fingerprints/face like providing a key: a physical characteristic, not testimony—so they’ve allowed warrants that compel a suspect’s thumbprint or face to unlock a phone.⁸

But in 2025 the D.C. Circuit held the opposite—compelled thumbprint unlocking was testimonial and violated the Fifth Amendment, deepening a clear conflict with decisions (including the Ninth Circuit’s 2024 ruling) that allowed compelled fingerprint unlocking under some facts.^9–10

Bottom line in Pennsylvania (today): there’s no precedential PA appellate ruling squarely approving or disapproving compelled biometrics. Expect litigation to cite the out-of-state split until Pennsylvania’s appellate courts (or the U.S. Supreme Court) give a definitive answer.

Fourth Amendment backdrop: warrants to search phones

Independently of the Fifth Amendment, the U.S. Supreme Court’s Riley v. California requires police to get a warrant to search the digital contents of a phone in nearly all situations, even after an arrest. Riley recognizes phones hold vast troves of private data and deserve heightened protection.^2–4

A warrant to search a phone doesn’t automatically authorize compelling you to help unlock it—those are separate constitutional questions (Fourth vs. Fifth Amendment).

Practical scenarios & defenses

·         “We have a phone, we have a warrant—tell us the passcode.”  In Pennsylvania, Davis bars compelling you to say the passcode. Suppression is likely if the Commonwealth tries to force verbal disclosure. ¹

·         “We have a warrant—give us your thumb/face.”  This currently sits in a gray zone in PA. Defense should challenge under the Fifth Amendment (testimonial act) and under the warrant’s scope/particularity. Cite the D.C. Circuit’s 2025 decision as persuasive authority; distinguish the Ninth Circuit’s 2024 ruling factually. ^9–10

·         “They looked at notifications without a phone warrant.”  Under Riley, even seemingly “small” peeks at on-screen content can be searches. Suppression arguments are strong where officers view or capture screen content without a phone-specific warrant. ^{2–4, 11}

For clients: simple precautions

1.    Use a strong passcode (not just biometrics). In Pennsylvania, a passcode gives you the most Fifth Amendment protection today. ¹

2.    Know your rights: You can decline to state or enter your passcode. Politely assert your right to counsel.

3.    Disable biometric unlock before encounters likely to involve seizure (e.g., at protests or during travel stops) if you want maximum protection given the national split.

4.    Do not consent to a “quick look.” Riley means a warrant is usually required to search phone contents. ^2–4

For lawyers: quick litigation checklist

• Fifth Amendment (testimonial act). Argue Davis for passcodes; extend its rationale to biometrics where the “act of unlocking” communicates control/knowledge linking the accused to the device and its incriminating contents (the D.C. Circuit’s Brown reasoning). ^{1, 9}

• Foregone conclusion limits. Emphasize Davis’s rejection of applying foregone conclusion to passwords; distinguish cases using it more broadly (e.g., Massachusetts). ^1,6

• Fourth Amendment. Enforce Riley: require a particularized phone warrant; attack scope (apps, clouds, time ranges), and argue the warrant does not authorize compelled unlocking by the suspect. ^2–4

• Factual development. Nail down how officers obtained access (voluntary entry, physical force with a thumb, face presentation, notification peeks), the timing relative to arrest, and whether any pre-unlock observations occurred without a phone warrant.

• Suppression remedies. Seek exclusion of both the compelled act and its fruits (Kastigar-style Fifth Amendment taint analysis where applicable).

  
  

When will this be resolved?

With the D.C. Circuit–Ninth Circuit split on biometrics, this is ripe for the U.S. Supreme Court to address. Until then, Pennsylvania firmly protects passcodes, while biometrics remain an open question under Pennsylvania law.

Sidebar: Quick FAQ

• Do I have to give my thumb or face if police have a warrant? Not settled in Pennsylvania. Some courts allow it; others (like the D.C. Circuit in 2025) say it’s testimonial and barred. ^9–10

• If they already have a warrant to search the phone, doesn’t that mean I must unlock it? No. A search warrant authorizes the government to search; it does not automatically compel you to assist. Fifth Amendment issues are separate. ^2–4

• Will turning off Face ID/Touch ID help? It can. Using a passcode (protected in PA) may strengthen your position if police try to compel unlocking. ¹

  
  

References

1. Commonwealth v. Davis, 220 A.3d 534 (Pa. 2019) — https://law.justia.com/cases/pennsylvania/supreme-court/2019/56-map-2018.html | Opinion PDF: https://www.aclupa.org/sites/default/files/field_documents/reversed_remanded.pdf | Case page: https://www.aclupa.org/cases/commonwealth-v-davis/

2. Riley v. California, 573 U.S. 373 (2014) — https://supreme.justia.com/cases/federal/us/573/373/ | PDF: https://supreme.justia.com/cases/federal/us/573/13-132/case.pdf

3. Riley explainer (EPIC) — https://epic.org/documents/riley-v-california-2/

4. Riley background memo — https://www.whiteandwilliams.com/media/alert/281_Riley%20and%20Wurie.pdf

5. Seo v. State, 148 N.E.3d 952 (Ind. 2020) — https://law.justia.com/cases/indiana/supreme-court/2020/18s-cr-595.html

6. State v. Andrews, 243 N.J. 447 (2020) — https://www.njcourts.gov/system/files/court-opinions/2020/a_72_18.pdf | Overview: https://epic.org/documents/state-v-andrews/

7. U.S. v. Payne, 69 F.4th 1189 (9th Cir. 2024) — https://www.sgoldsobel.com/important-to-know-law-enforcement-can-use-biometric-data-to-unlock-smartphones/ | Split explainer: https://idtechwire.com/appeals-courts-split-lays-the-groundwork-for-scotus-case-on-biometric-cell-phone-unlocking/

8. District-court line allowing compelled biometrics (illustrative) — https://www.biometricupdate.com/201912/federal-state-court-rulings-on-whether-biometrics-protected-by-fifth-amendment-get-murky

9. U.S. v. Brown, 125 F.4th 1186 (D.C. Cir. 2025) — https://www.arnoldporter.com/en/perspectives/advisories/2025/03/when-your-fingers-do-the-talking | https://www.criminallegalnews.org/news/2025/feb/15/dc-circuit-holds-compelling-suspect-unlock-cellphone-thumbprint-testimonial-act-and-violates-fifth-amendment-privilege-against-self-incrimination/ | https://www.police1.com/legal/compelling-a-thumbprint-to-unlock-phone-violated-fifth-amendment

10. Split overview (2025) — https://cdt.org/insights/circuit-court-split-lays-the-groundwork-for-scotus-case-on-biometric-cell-phone-unlocking/

11. PA example post-Riley (practitioner write-up) — https://goldsteinmehta.com/blog/pennsylvania-superior-court-affirms-suppression-of-cell-phone-evidence-in-drug-case-because-police-looked-at-phone-screen-without-warrant

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