Limits on Good-Faith Reliance and Tainted Affidavits: Excluding Evidence from Overbroad State Warrants

Introduction

United States v. Santiago (10th Cir., Apr. 30, 2025) addresses the Fourth Amendment’s particularity requirement, the scope of the good-faith exception to the exclusionary rule, and the consequences of using evidence obtained under an overbroad state warrant to support a later federal warrant. Alexander William Santiago was arrested under Oklahoma state charges for statutory rape and lewd acts with a minor. Officers seized his iPhone without a warrant, then obtained and executed a broad state‐court warrant, which yielded child pornography images. Federal agents used those images to secure a federal warrant and ultimately convicted Mr. Santiago of production and possession of child pornography. On appeal, the Tenth Circuit held the state warrant impermissibly overbroad, that no objectively reasonable officer could rely on it, and that the tainted state‐search results could not support a valid federal search warrant.

Summary of the Judgment

The panel, sitting en banc for a three-judge hearing, reversed the district court’s denial of Mr. Santiago’s suppression motion. It concluded:

The state search warrant violated the Fourth Amendment’s particularity requirement by authorizing a general, carte-blanche search of Mr. Santiago’s iPhone.
The Leon good‐faith exception does not apply where a warrant is so plainly overbroad that no reasonable officer could rely on it.
All evidence derived from the state warrant must therefore be suppressed.
Without the tainted evidence, the federal affidavit lacked probable cause to support a warrant for child pornography, so evidence from the federal search must also be excluded.
The convictions and sentences were vacated, and the case remanded for further proceedings.

Analysis

Precedents Cited

United States v. Leon, 468 U.S. 897 (1984) – Established the “good-faith exception,” under which evidence obtained in objectively reasonable reliance on a warrant is not excluded even if the warrant is later invalidated.
Groh v. Ramirez, 540 U.S. 551 (2004) – Clarified that a warrant lacking particularity cannot be cured by good faith; no reasonable officer could believe a facially unconstitutional warrant is valid.
Cassady v. Goering, 567 F.3d 628 (10th Cir. 2009) – Held that a warrant authorizing seizure of “all other evidence” of criminal activity is overbroad, and officers cannot rely on such a warrant in good faith.
Maryland v. Garrison, 480 U.S. 79 (1987) – Emphasized the Fourth Amendment’s particularity requirement to prevent general searches.
United States v. Mora, 989 F.3d 794 (10th Cir. 2021) – Instructed courts to excise unlawfully obtained information from affidavits and reassess probable cause.

Legal Reasoning

1. Particularity Requirement
The Fourth Amendment mandates that a warrant “particularly describ[e] the place to be searched and the things to be seized.” The state warrant at issue authorized officers to search every data category on Mr. Santiago’s phone “as well as any other information . . . that may be deemed evidence.” That language converted a targeted search into an unrestricted fishing expedition, directly contravening Garrison and its progeny.

2. Good-Faith Exception Does Not Apply
Under Leon, exclusion is inappropriate when officers rely in good faith on a warrant. However, the Tenth Circuit emphasized that where a warrant is so lacking in particularity that no reasonable officer could think it valid—per Groh and Cassady—the exception is unavailable. Here, the warrant’s facial overbreadth, copied verbatim from the police affidavit, amounted to police misconduct, triggering the exclusionary rule.

3. Subsequent Federal Warrant
Mora requires excising unlawfully obtained evidence from affidavits. Removing all references to child pornography discovered under the state warrant, the federal affidavit described only a consensual relationship and unremarkable communications. That scenario, without additional indicia of illicit materials, failed to establish probable cause for a child‐pornography search. The federal search was thus unconstitutional and its fruits must be suppressed.

Impact

United States v. Santiago tightens the standard for reliance on state warrants and underscores that:

Officers must ensure warrants comply strictly with the Fourth Amendment’s particularity requirement before executing searches.
Courts will not excuse overbroad warrants via the good-faith exception if the overbreadth is obvious.
Evidence obtained under an unconstitutional state search cannot bootstrap probable cause for a federal warrant.

This decision will influence law enforcement practices, warrant drafting, and suppression motions in both state and federal prosecutions, particularly in investigations involving digital devices and data.

Complex Concepts Simplified

Particularity Requirement: A warrant must clearly state exactly what will be searched and seized—no “anything else” catch-all language.
Good-Faith Exception: Normally, evidence gathered under a warrant is admissible if officers acted reasonably, even if the warrant is later invalidated. But if the warrant is obviously defective, this rule does not apply.
Tainted Affidavit Doctrine: If a later warrant relies on evidence obtained under an illegal search, the court must remove (“excise”) that tainted information and see if what remains still shows probable cause.

Conclusion

United States v. Santiago establishes that warrants must be drafted with precise scope, and that officers cannot hide behind the good-faith exception when executing warrants so overbroad that invalidity is patent. Furthermore, evidence obtained through such unconstitutional warrants cannot support subsequent searches. This ruling reinforces robust protection of privacy in the digital age and will guide future courts in evaluating both state and federal warrants.