Probable Cause + Imminent Digital Deletion Permits Warrantless Cell-Phone Seizure; Non-Material Franks Errors Do Not Invalidate a Later Search Warrant

I. Introduction

In United States v. Amir Kalomo Mulamba (8th Cir. Aug. 12, 2026), the Eighth Circuit affirmed the denial of a motion to suppress evidence obtained from a cell phone that officers seized during an in-home interview and later searched pursuant to a warrant. The case began when a mother (A.R.) reported that an adult had offered her sixteen-year-old daughter (E.R.) vape pens in exchange for sex via Snapchat. Investigators linked the Snapchat account (“Amiro Fenomeno”) and a described vehicle to Amir Mulamba.

The appeal presented two Fourth Amendment questions: (1) whether officers could seize Mulamba’s phone without a warrant based on probable cause and exigency (fear of imminent evidence destruction), and (2) whether the later search warrant was invalid under Franks v. Delaware because the affidavit omitted and misstated certain details.

II. Summary of the Opinion

The court held that the warrantless seizure was reasonable because officers had (i) probable cause to believe the phone contained evidence of attempted sex trafficking of a minor under 18 U.S.C. §§ 1591 and 1594, and (ii) exigent circumstances because Mulamba appeared to be deleting phone content while officers questioned him. The court also rejected Mulamba’s Franks challenge because, even correcting the alleged omissions/misstatement in the affidavit, the warrant still established probable cause.

Judge Kelly dissented, concluding probable cause was lacking and cautioning against treating deletion of phone content—given the breadth of private data on smartphones—as inherently indicative of criminality.

III. Analysis

A. Precedents Cited

  • Illinois v. McArthur, 531 U.S. 326 (2001)
    Cited for the baseline rule that seizures of personal property generally require a warrant and are otherwise “unreasonable” absent an exception. The majority used it as the starting point before moving to exigency.
  • United States v. Shrum, 59 F.4th 968 (8th Cir. 2023)
    Provided the key exception: warrantless seizure of property is permissible where officers have probable cause and exigent circumstances requiring immediate action. This framed the two-part test the majority applied.
  • United States v. Ball, 90 F.3d 260 (8th Cir. 1996)
    Established the appellate review framework: historical facts for clear error; ultimate determinations of probable cause/exigency reviewed de novo from the perspective of an objectively reasonable officer.
  • United States v. Mays, 993 F.3d 607 (8th Cir. 2021) and United States v. Andrews, 454 F.3d 919 (8th Cir. 2006)
    Supplied the “totality of the circumstances” definition of probable cause and the timing/knowledge lens—probable cause is assessed based on facts known at the time of the seizure.
  • United States v. Meyer, 19 F.4th 1028 (8th Cir. 2021)
    Used to reinforce that probable cause does not require ruling out innocent explanations for suspicious facts—supporting the majority’s reliance on deletion behavior in context.
  • United States v. Wolff, 796 F.3d 972 (8th Cir. 2015) (per curiam)
    Cited as an example applying 18 U.S.C. § 1591 principles; it bolstered the majority’s conclusion that the facts supported probable cause for attempted child sex trafficking.
  • United States v. Stevens, 530 F.3d 714 (8th Cir. 2008) and United States v. Robertson, 39 F.3d 891 (8th Cir. 1994)
    Guided the treatment of an identified citizen-informant’s report (A.R.) as bearing “indicia of reliability,” including in-person reporting, detail, and corroboration of “even innocent, minor details.”
  • United States v. Reiner Ramos, 818 F.2d 1392 (8th Cir. 1987) and United States v. Mayo, 627 F.3d 709 (8th Cir. 2010)
    Supported considering “furtive gestures” and “nervous behavior” as part of the probable-cause mosaic.
  • United States v. McKinney, 980 F.3d 485 (5th Cir. 2020)
    Cited for the general proposition that attempts to hide or discard contraband can contribute to suspicion/probable cause; the majority used it to contextualize deletion as potentially consciousness of guilt.
  • United States v. Ramirez, 676 F.3d 755 (8th Cir. 2012), United States v. Evans, 178 F.4th 416 (8th Cir. 2026)
    Provided the exigency standard: whether a reasonable, experienced officer would believe evidence is about to be destroyed—applied to real-time deletion during questioning.
  • Franks v. Delaware, 438 U.S. 154 (1978) and Briscoe v. St. Louis Cnty., 172 F.4th 996 (8th Cir. 2026)
    Supplied the two-part invalidation test for false statements/omissions: intentional/reckless falsity or omission, plus materiality (probable cause fails once corrected). The majority resolved the issue on the second prong (materiality).
  • United States v. Johnson, 75 F.4th 833 (8th Cir. 2023)
    Cited for standards of review on Franks issues (fact findings vs. legal conclusions).
  • United States v. Summage, 481 F.3d 1075 (8th Cir. 2007)
    Supported the point that an affidavit need not name the specific crime; it suffices to allege facts establishing probable cause that the conduct is criminal.
  • United States v. Kucharo, 127 F.4th 1152 (8th Cir. 2025)
    Reinforced the “fair probability” articulation for probable cause in assessing the corrected affidavit.
  • Dissent authorities: Bowden v. Meinberg, 807 F.3d 877 (8th Cir. 2015); Warren v. City of Lincoln, 864 F.2d 1436 (8th Cir. 1989); Webster v. Westlake, 41 F.4th 1004 (8th Cir. 2022); United States v. Mendenhall, 446 U.S. 544 (1980); Riggs v. Gibbs, 923 F.3d 518 (8th Cir. 2019); United States v. Sanders, 424 F.3d 768 (8th Cir. 2005); Riley v. California, 573 U.S. 373 (2014)
    These were marshaled to stress that citizens may terminate voluntary encounters, withdraw consent, and that smartphones contain vast private information—making deletion ambiguous and cautioning against over-reading it as criminal.

B. Legal Reasoning

1. Warrantless seizure: probable cause + exigency

The majority treated the seizure as justified under the United States v. Shrum framework: (a) probable cause to believe the phone contained evidence, and (b) exigent circumstances requiring immediate seizure to prevent destruction.

Probable cause. The court identified a “fair probability” the phone contained evidence that Mulamba attempted to solicit a minor for a commercial sex act (18 U.S.C. §§ 1591, 1594). The totality included: (i) A.R.’s in-person report of a quid pro quo (vapes for sex) with corroborated details (vehicle/license plate); (ii) E.R.’s account of an adult meeting her at her home, giving her a vape, sending sexualized messages, and knowing she was 16; (iii) linkage of “Amiro Fenomeno” to Mulamba; and (iv) Mulamba’s conduct during the interview—shielding the screen and admitting he was deleting items when officers asked about “E.”

The court rejected Mulamba’s attempt to characterize inconsistencies (sex vs. “make out,” lack of explicit quid pro quo messages) as negating probable cause, reasoning officers could infer missing content from deleted messages and could credit A.R.’s account as reliable and corroborated. It also emphasized, via United States v. Meyer, that officers need not eliminate innocent explanations for suspicious facts.

Exigent circumstances. Applying United States v. Ramirez, the court held a reasonable, experienced officer would believe evidence destruction was imminent because Mulamba appeared to delete content in real time after recognizing officers were focused on “E,” and because earlier messages had already been deleted from Snapchat. That combination—probable cause plus imminent digital destruction—made immediate seizure reasonable despite the lack of a warrant at that moment.

2. The Franks challenge: materiality controls

Mulamba argued the search-warrant affidavit was defective because it (i) omitted that his consent was obtained only after agents inaccurately answered “Yep” when asked if they had a warrant; (ii) omitted E.R.’s statement that she had only sent nude photos to another teenager; and (iii) overstated the time it took to retrieve the phone (nine minutes vs. three).

The majority resolved the Briscoe v. St. Louis Cnty. test on the second prong: even if the affidavit were corrected with the omitted facts and the timing fixed, it would still establish probable cause to search for evidence of attempted sex trafficking. Critically, the alleged omissions did not undermine the core nexus between Mulamba, the “Amiro Fenomeno” account, the minor, the meeting, and the sexually charged communications—nor the evidence-preservation concern raised by deletion attempts. The court also noted, via United States v. Summage, that the affidavit need not label the exact criminal statute if the facts show criminal conduct.

3. The dissent’s competing Fourth Amendment framing

Judge Kelly’s dissent took a narrower view of probable cause, stressing (i) the lack of documentary proof of an explicit “vapes for sex” bargain, (ii) E.R.’s initial statement that he asked for nothing in return for the vape, and (iii) the risk of treating phone-deletion behavior as inherently incriminating given the privacy and breadth of information recognized in Riley v. California. The dissent emphasized that in a voluntary encounter, a person may stop sharing information and may withdraw consent, and warned that “deleting some personal information” does not automatically imply contraband without a prior foundation that the deleted content is evidence.

C. Impact

  • Digital-evidence exigency in the interview room (or living room). The decision strengthens the government’s position that when probable cause already exists and officers observe real-time deletion, they may seize a phone immediately to preserve evidence, even before obtaining a warrant.
  • “Buttoning up” with a warrant remains valuable. Even where officers have a signed consent, pursuing a warrant can reduce litigation risk; here it shifted the decisive fight to Franks materiality.
  • Franks litigation focus: materiality first. The court’s approach—declining to decide intent/recklessness because probable cause survived correction—encourages future courts and litigants to address whether alleged misstatements/omissions actually change the probable-cause calculus.
  • Limits and fault lines. The dissent highlights a developing tension after Riley v. California: courts may diverge on how much weight to give smartphone-deletion behavior, especially where the underlying evidence of criminal conduct is less corroborated than in Mulamba.

IV. Complex Concepts Simplified

  • Probable cause: Not proof beyond a reasonable doubt—just a “fair probability” that evidence of a crime will be found in a particular place.
  • Exigent circumstances: Emergency conditions that make waiting for a warrant unreasonable—here, a reasonable belief evidence will be destroyed imminently.
  • Seizure vs. search: Taking control of an item (seizure) is distinct from examining its contents (search). A phone may be seized to preserve evidence while officers seek a search warrant.
  • Franks hearing/challenge: A defendant can attack a warrant by showing intentional or reckless falsehoods/omissions in the affidavit that were material—i.e., without them, probable cause would fail.
  • Attempted sex trafficking of a minor (18 U.S.C. §§ 1591, 1594): Federal law can criminalize attempting to induce a person under 18 to engage in a commercial sex act, regardless of state “age of consent” rules.
  • Fruit of the poisonous tree: Evidence derived from an unlawful seizure/search may be excluded. The dissent noted the parties agreed the warrant would fall if the initial seizure were unlawful.
  • Conditional guilty plea (Fed. R. Crim. P. 11(a)(2)): Allows pleading guilty while preserving the right to appeal a specified pretrial ruling (here, suppression).

V. Conclusion

United States v. Mulamba affirms a practical rule for digital investigations: when officers already have probable cause that a phone contains evidence of a crime and they observe conduct indicating imminent deletion, they may seize the phone without a warrant to preserve evidence. The case also underscores the limits of Franks v. Delaware challenges where alleged omissions or misstatements do not change the bottom-line probable-cause showing in the affidavit. At the same time, the dissent signals an important caution for future cases: given the uniquely private and expansive nature of smartphones recognized in Riley v. California, courts must be careful not to treat ordinary privacy-protective behavior—like deleting personal content—as a substitute for a robust probable-cause foundation.