Franks Violation

What It Is

A Franks violation occurs when an officer includes material false statements — or omits critical facts — in a warrant affidavit, and the warrant would not have been issued without the falsehood. The name comes from Franks v. Delaware, 438 U.S. 154 (1978).

In plain terms: if a police officer lied to get a search warrant, or deliberately left out information that would have changed the judge’s mind, the warrant — and everything found because of it — may be invalid.

The Two-Part Test

To establish a Franks violation, you must show:

1. The officer made a false statement (or omission) knowingly, intentionally, or with reckless disregard for the truth — Honest mistakes don’t count. You need to show the officer either knew the statement was false or didn’t care whether it was true.

2. The false statement was material — If you remove the lie (or add back the omitted information), the remaining affidavit doesn’t support probable cause. In other words, the falsehood actually mattered to the judge’s decision.

How to Raise a Franks Challenge

In criminal cases, defendants request a “Franks hearing” to challenge the warrant. In a § 1983 civil rights case, the Franks analysis works differently — you’re suing the officer for violating the Fourth Amendment by obtaining a warrant through deception.

You’ll need evidence showing what the officer said in the affidavit versus what actually happened. Useful sources include:

• Body camera footage contradicting the affidavit
• Witness statements that differ from what the officer claimed
• Police reports that conflict with the affidavit
• Records showing the officer omitted exculpatory information

Why It Matters in § 1983 Cases

Officers who fabricate warrant affidavits are not protected by qualified immunity in most circuits — it has been clearly established for decades that lying to obtain a warrant violates the Fourth Amendment. See Malley v. Briggs, 475 U.S. 335 (1986).

Common scenarios:

• Fabricated informant tips — The officer claimed an informant provided information that didn’t exist
• Exaggerated observations — The officer inflated what they saw to manufacture probable cause
• Omitted contradictory evidence — The officer knew facts that undermined probable cause but left them out
• Stale information presented as current — Using old information as if it were fresh

Key Cases

• Franks v. Delaware, 438 U.S. 154 (1978) — Established the right to challenge warrant affidavits containing deliberate falsehoods
• Malley v. Briggs, 475 U.S. 335 (1986) — Officers can be liable for obtaining a warrant no reasonable officer would have sought
• Kalina v. Fletcher, 522 U.S. 118 (1997) — No absolute immunity for officers who prepare false warrant affidavits