Cloud-Account Warrants Must Be Particularized, But Officers May Receive Leon Good-Faith Protection; Rule 12 Severance “Reasonably Available” Determinations Reviewed for Abuse of Discretion — United States v. Tew (10th Cir. Apr. 6, 2026)

1. Introduction

Parties: The United States prosecuted spouses Kimberley Ann Tew and Michael Aaron Tew for a multi-year invoicing and money-laundering scheme involving National Air Cargo (“National”), a government contractor. A National insider, Jonathan Yioulos, participated and later cooperated.

Background: After Michael Tew served as National’s CFO (and later was fired), the Tews—assisted by Yioulos—submitted false invoices for nonexistent vendors and obtained more than $5 million. The defendants each gave proffers that inculpated the other; at trial they advanced blame-shifting defenses.

Key issues on appeal:

  • Fourth Amendment / cloud search: Whether a Stored Communications Act warrant served on Apple for Kimberley’s cloud-based account was sufficiently particularized; if not, whether the United States v. Leon good-faith exception saved the evidence.
  • Severance: Whether severance should have been granted given antagonistic defenses, and whether the severance motions were timely under Fed. R. Crim. P. 12 and 14.

2. Summary of the Opinion

The Tenth Circuit affirmed both convictions. It held:

  • Apple warrant: The warrant was insufficiently particularized (overbroad in practical effect) because it authorized review/seizure of vast categories of cloud data while being limited primarily by very broad “Target Offenses” and an ambiguous start date. However, suppression was unwarranted because the Government met its burden to show good-faith reliance on the magistrate-issued warrant.
  • Severance: Kimberley’s severance theory was waived/forfeited because she did not seek a ruling on the post-cross-examination “antagonistic defenses” theory and did not argue plain error (and did not show good cause). Michael’s mid-trial severance motion was untimely because the basis was “reasonably available” pretrial; the panel treated the district court’s “reasonably available” determination as reviewed for abuse of discretion. Even on the merits, neither defendant satisfied the Tenth Circuit’s demanding severance standard for “mutually exclusive” defenses.

3. Analysis

3.1. Precedents Cited

Particularity and digital searches

  • United States v. Palms, 21 F.4th 689 (10th Cir. 2021)
    Used for the governing particularity standard and the idea that warrants must provide “practical guidelines” leaving “nothing to the discretion” of executing officers. Also supplied the standard of review for suppression rulings (facts viewed favorably to the government; legal questions de novo).
  • United States v. Otero, 563 F.3d 1127 (10th Cir. 2009)
    Anchored the court’s heightened sensitivity to particularity in the digital context; the panel extended Otero’s insight (intermingling of personal data) to the far more expansive reality of cloud accounts.
  • United States v. Carey, 172 F.3d 1268 (10th Cir. 1999)
    Cited for the categorical difference between searching computers and physical containers—supporting the panel’s further move: cloud-account searches are categorically different even from device searches because they can unify data across devices and time.
  • United States v. Suggs, 998 F.3d 1125 (10th Cir. 2021)
    Supplied the “as much specificity as the government’s knowledge and circumstances allow” formulation and the formal rule for using an affidavit to cure a warrant: the affidavit must be attached and expressly incorporated in the warrant (both missing here).
  • United States v. Cooper, 654 F.3d 1104 (10th Cir. 2011)
    Provided (i) that an affidavit can particularize a warrant only under strict conditions, and (ii) that particularity analysis depends in part on the nature/complexity of the crime—though complexity does not justify unbounded seizure authority.
  • United States v. Leary, 846 F.2d 592 (10th Cir. 1988)
    Central to the holding that “unadorned reference” to broad federal statutes does not sufficiently limit a warrant. The panel relied on Leary to reject the Government’s argument that listing sweeping “Target Offenses” (including conspiracy and wire fraud) was a meaningful constraint.
  • United States v. Loera, 923 F.3d 907 (10th Cir. 2019)
    Cited for de novo review of particularity and good faith.
  • Maryland v. Garrison, 480 U.S. 79 (1987)
    Quoted through Otero for the historical purpose of particularity: preventing “exploratory searches” associated with general warrants.
  • Coolidge v. New Hampshire, 403 U.S. 443 (1971)
    Used for the “exploratory rummaging” concern that resonates strongly where cloud data can expose communications, location history, and photos at scale.
  • Riley v. California, 573 U.S. 373 (2014)
    Not dispositive (because a warrant existed here), but crucial to framing why modern digital repositories are uniquely intrusive and why expansive access can exceed even an exhaustive home search.
  • Carpenter v. United States, 585 U.S. 296 (2018)
    Used to emphasize that the Fourth Amendment must respond to technology-enabled surveillance and aggregation; reinforced skepticism of broad, retrospective access to location and activity histories.
  • Kyllo v. United States, 533 U.S. 27 (2001)
    Quoted via Carpenter for preserving “that degree of privacy” that existed at the Founding in the face of technological change.
  • United States v. Blake, 868 F.3d 960 (11th Cir. 2017)
    Persuasive authority highlighting constitutional concerns where social-media warrants demand “virtually every type of data” in an account; used to situate cloud-account warrants among modern “general warrant” risks.
  • United States v. Zelaya-Veliz, 94 F.4th 321 (4th Cir. 2024)
    Persuasive authority warning that a lack of time limits in account warrants is problematic because accounts can contain “decades” of data; supported the panel’s concerns even though Apple accounts may be more expansive than social media.
  • United States v. Wagner, 951 F.3d 1232 (10th Cir. 2020)
    The Government invoked Wagner (warrant read “as a whole” may sufficiently limit), but the panel distinguished it: here only one exemplar paragraph referenced National, while the rest effectively rode on broad “Target Offenses.”
  • United States v. Porter, 745 F.3d 1035 (10th Cir. 2014)
    Used for the interpretive point that “including” clauses are typically non-exhaustive; this supported the court’s conclusion that the National reference did not meaningfully cabin the warrant’s overall scope.
  • Kousisis v. United States, 605 U.S. 114 (2025) and Pasquantino v. United States, 544 U.S. 349 (2005)
    Quoted to underscore that the wire fraud statute’s breadth is well recognized, making it an especially weak limiting principle for particularity.

Good faith and the exclusionary rule

  • United States v. Leon, 468 U.S. 897 (1984)
    Provided the foundational good-faith exception: magistrate-issued warrants carry a presumption of reasonableness unless reliance is objectively unreasonable.
  • Mapp v. Ohio, 367 U.S. 643 (1961)
    Cited for the rationale of the exclusionary rule as a deterrence mechanism rather than a personal constitutional right to suppression in every instance.
  • United States v. Cardall, 773 F.2d 1128 (10th Cir. 1985)
    Used for the presumption of good faith when officers rely on a warrant signed by a neutral magistrate.
  • United States v. Knox, 883 F.3d 1262 (10th Cir. 2018)
    Quoted for the premise that officers generally need not second-guess a magistrate’s technical sufficiency determination.
  • United States v. Corral-Corral, 899 F.2d 927 (10th Cir. 1990)
    Emphasized the limit: some warrants are so deficient that good faith is “wholly unwarranted.”
  • United States v. Riccardi, 405 F.3d 852 (10th Cir. 2005) and United States v. Russian, 848 F.3d 1239 (10th Cir. 2017)
    Provided the contextual factors used to evaluate objective reasonableness (e.g., whether the affiant also executed; magistrate signed the affidavit; consultation with counsel; steps to limit improper review).
  • United States v. Santiago, 135 F.4th 1235 (10th Cir. 2025) and Groh v. Ramirez, 540 U.S. 551 (2004)
    Supplied the “plainly” deficient warrant concept: if the warrant obviously fails particularity, no reasonable officer could rely on it. The panel distinguished the Apple warrant from the more glaring defects in Santiago and Groh.
  • United States v. Grimmett, 439 F.3d 1263 (10th Cir. 2006)
    Cited via Palms for suppression review standards.

Severance, preservation, and timeliness

  • United States v. Pursley, 474 F.3d 757 (10th Cir. 2007)
    The controlling three-step severance framework: (1) mutually exclusive defenses; (2) serious risk to a trial right or to reliable verdict; (3) prejudice balanced against judicial economy.
  • Zafiro v. United States, 506 U.S. 534 (1993)
    Underwrote the principle that mutually antagonistic defenses are not prejudicial per se.
  • United States v. Jones, 530 F.3d 1292 (10th Cir. 2008) and United States v. Dazey, 403 F.3d 1147 (10th Cir. 2005)
    Supplied the “mutually exclusive” test: the jury must have to disbelieve the core of one defense to believe the other.
  • United States v. Linn, 31 F.3d 987 (10th Cir. 1994)
    Reinforced that “finger pointing” is usually insufficient for severance.
  • Bruton v. United States, 391 U.S. 123 (1968)
    Relevant as the distinct pretrial theory Kimberley raised (Confrontation Clause risk from a codefendant’s statements), which did not preserve her later Pursley-based “antagonistic defenses” theory without a requested ruling.
  • U.S. Aviation Underwriters, Inc. v. Pilatus Bus. Aircraft, Ltd., 582 F.3d 1131 (10th Cir. 2009) and United States v. Leffler, 942 F.3d 1192 (10th Cir. 2019)
    Used to explain forfeiture/waiver on appeal: a party must alert the district court and seek a ruling; if not preserved and no plain-error argument is made, review is typically declined.
  • United States v. Herrera, 51 F.4th 1226 (10th Cir. 2022) and United States v. Bowline, 917 F.3d 1227 (10th Cir. 2019)
    Established that the Tenth Circuit will not review untimely Rule 12 motions “in the absence of good cause,” and that good-cause determinations are reviewed for abuse of discretion.
  • United States v. Burrage, 75 F.4th 953 (8th Cir. 2023)
    Persuasive authority supporting abuse-of-discretion review for Rule 12 untimeliness determinations—used by the panel in adopting that standard for “reasonably available” severance timing.
  • United States v. Hargrove, 911 F.3d 1306 (10th Cir. 2019)
    Invoked to presume juries follow limiting instructions; the acquittal on one Kimberley count supported the view the jury compartmentalized evidence.

3.2. Legal Reasoning

A. The cloud-account warrant: why it failed particularity

The court emphasized that cloud-account warrants present a distinctive Fourth Amendment risk: they can expose years of “intermingled” communications, photos, and location history across multiple devices, through a single account credential. Building from Riley v. California and Carpenter v. United States, the panel treated the breadth of modern digital records as the core reason that particularity “matters more,” not less.

The Apple warrant’s defect was structural and textual:

  • The affidavit could not cure the warrant. Under United States v. Suggs, an affidavit can particularize only if attached to the warrant and expressly incorporated; here it was attached/incorporated to the application, not the warrant.
  • “Target Offenses” were too broad to meaningfully limit. Citing United States v. Leary, the court reiterated that bare reference to broad statutes (e.g., conspiracy, wire fraud) does not adequately cabin officers’ discretion, especially when the warrant effectively authorizes seizure of any “fruits, evidence and/or instrumentalities” of those offenses.
  • “Including” language signaled non-exhaustive scope. Applying United States v. Porter, the court read the warrant’s examples (“including” the National scheme) as illustrative, not limiting—so the National reference did not confine the remainder.
  • The time limitation did little work. The start date was ambiguous (evidence created after the date vs. evidence “of” crimes occurring after the date), and the “motive” language risked sweeping in intimate marital communications unrelated to the charged scheme.
  • The warrant could have been narrowed with known information. The affidavit identified people and accounts that could have supported tighter ex ante constraints (e.g., specific correspondents, names, or account identifiers), which underscored that the lack of narrowing was not technologically inevitable.

On this reasoning, the panel held the Apple warrant violated the Fourth Amendment’s particularity requirement.

B. Why the evidence was still admissible: good faith as a “close call”

Despite finding a constitutional defect, the panel applied United States v. Leon and held officers acted in objectively reasonable reliance on a magistrate-issued warrant. Critically, the court distinguished warrants that are “plainly” deficient (where no reasonable officer could rely) from warrants that are defective only after careful legal parsing.

The court explained why this was not a Groh v. Ramirez or United States v. Santiago case: unlike those warrants, the Apple warrant did list items and referenced the crimes under investigation—its failure was overbreadth and insufficient limiting principles, not a glaring omission apparent on a “simple glance.”

Contextual factors (from United States v. Riccardi and United States v. Russian) supporting good faith included:

  • The magistrate judge signed the warrant, application, and affidavit (supporting an inference that the judge considered the affidavit when issuing the warrant).
  • The application noted review by an Assistant U.S. Attorney (suggesting officers sought legal input).
  • The executing agent had ongoing involvement in the same investigation (suggesting familiarity with evidentiary limits).
  • Agents used a taint protocol to avoid privileged review (some evidence of compliance-minded execution).

The panel candidly described the outcome as “a close call,” highlighting the lack of on-point precedent about properly limiting cloud-account warrants—an observation that both justified the officers’ reliance and signaled the court’s expectation that future warrants be drafted with tighter guardrails.

C. Severance: preservation, timeliness, and merits

Kimberley Tew

Kimberley’s appeal failed primarily on preservation. While she raised a pretrial severance motion, it was grounded in Bruton v. United States (Confrontation Clause concerns). Her later, trial-stage complaint concerned Pursley-type antagonistic defenses. The panel treated that as a distinct theory requiring her to seek a ruling on that theory, which she did not.

Because she did not request a ruling and did not argue plain error in her opening brief, the court applied Tenth Circuit forfeiture/waiver principles (citing United States v. Leffler) and declined review—also noting the separate “good cause” barrier for untimely Rule 12 motions (citing United States v. Herrera).

Even if reached, the panel found minimal prejudice because the jury instructions required separate consideration and the verdict itself showed compartmentalization: Kimberley was acquitted on one money-laundering count while Michael was convicted, supporting the presumption from United States v. Hargrove that juries follow instructions.

Michael Tew

Michael did move for severance during trial, but the court held it was untimely under Rule 12 because the basis was “reasonably available” pretrial. The panel made two precedent-significant moves:

  • Interpreting “reasonably available”: The defendant need not know with certainty how antagonistic defenses will unfold; it is enough that the risk was apparent “at least at a high level,” given the case history (mutually inculpatory proffers, prior conflict warnings, and pretrial severance litigation).
  • Standard of review: The panel treated “reasonably available” determinations as mixed fact-law judgments best assessed by the trial judge and adopted abuse of discretion review (citing the Eighth Circuit’s United States v. Burrage for support).

The court rejected Michael’s “good cause” claim, reasoning that “non-frivolity” on the merits cannot itself excuse untimeliness without nullifying Rule 12’s timing requirement.

On the merits (addressed alternatively), the panel applied United States v. Pursley and held the defenses were not “mutually exclusive” under United States v. Jones and United States v. Dazey; they were classic “finger pointing” under United States v. Linn. The court also emphasized judicial economy: granting severance mid-trial would require mistrial and duplicative proceedings after years of delay.

3.3. Impact

Fourth Amendment / digital evidence

  • Doctrinal signal on cloud warrants: The opinion squarely recognizes cloud-account searches as categorically distinct and especially privacy-invasive, extending the logic of Riley v. California and Carpenter v. United States into Stored Communications Act practice.
  • Drafting guidance (implicit but clear): Warrants should not rely primarily on broad “Target Offenses” (conspiracy, wire fraud, money laundering) as the limiting principle. Expect future litigants to cite Tew to demand tighter limitations such as named victims/schemes, narrower date ranges, identified correspondents, account identifiers, and crime-specific nexus language.
  • Good faith remains powerful—yet narrows going forward: The court’s “close call” good-faith holding is likely time-sensitive: once Tew exists, officers in the Tenth Circuit have clearer notice that broad cloud-account warrants risk invalidation, making future good-faith reliance harder to establish when similar overbreadth persists.

Criminal procedure / severance

  • Earlier severance litigation pressure: Defendants anticipating blame-shifting must raise severance earlier; waiting for openings or cross-examination risks Rule 12 untimeliness.
  • Appellate posture hardens: The decision reinforces that severance arguments are easy to lose on preservation grounds—especially where a defendant “makes a record” but fails to seek a ruling or fails to brief plain error.
  • Standard-of-review clarification: By adopting abuse-of-discretion review for the “reasonably available” timeliness determination, Tew gives district judges substantial leeway to enforce Rule 12’s timing discipline.

4. Complex Concepts Simplified

  • “Particularity”: A warrant must say specifically what officers may search for and seize, so officers are not free to rummage through everything hoping to find something incriminating.
  • “Stored Communications Act” warrants and the “two-step” process: Officers often first compel a provider (like Apple) to disclose large sets of account data, then officers themselves filter what may actually be seized/used as evidence. That filtering step makes warrant limits especially important because disclosure can be extremely broad.
  • “Good faith” (the Leon exception): Even if a warrant is later found unconstitutional, evidence may still be used if reasonable officers relied on the judge’s warrant and the defect was not so obvious that reliance was objectively unreasonable.
  • “Severance”: Trying codefendants separately. Courts prefer joint trials for co-conspirators, and severance is generally granted only when a joint trial threatens a concrete trial right or makes a reliable verdict unlikely.
  • “Mutually exclusive defenses”: Not just “we blame each other,” but a situation where believing one defendant’s core story necessarily means the other defendant’s core story must be false.
  • “Forfeiture/waiver” on appeal: To raise an argument on appeal, a party generally must ask the trial judge to decide it. If the party fails to do so (and fails to argue plain error), the appellate court will usually refuse to consider it.

5. Conclusion

United States v. Tew establishes two practically significant teachings in the Tenth Circuit. First, cloud-account warrants that effectively authorize broad review and seizure of years of intensely personal data—limited mainly by broad federal statutes—can violate the Fourth Amendment’s particularity requirement, even though evidence may still be admitted under the Leon good-faith exception in a close, precedent-scarce setting. Second, severance disputes are governed as much by timing and preservation as by prejudice: the “reasonably available” basis for severance must be raised before trial, district courts have broad discretion to enforce Rule 12, and antagonistic-defenses severance remains a demanding showing on the merits.