Tenth Circuit Clarifies Officer Liability for Prolonged Prone Restraints and Failure-to-Intervene
Commentary on Krueger v. Phillips, ___ F.4th ___ (10th Cir. Aug. 22 2025)

1. Introduction

Krueger v. Phillips is the latest in a line of Tenth Circuit decisions examining police use of force during arrests and the scope of qualified immunity. The Court of Appeals affirmed the denial of qualified immunity to eight law-enforcement officers who allegedly (i) removed Jeffrey Krueger from his vehicle by his hair, slammed his head onto pavement and repeatedly applied tasers; (ii) later pinned the hand-cuffed, shackled and prone Mr Krueger under several officers’ body weight for minutes; and (iii) failed to intervene while the force was used. Mr Krueger died at the scene.

Beyond its tragic facts, the judgment establishes two important doctrinal refinements:

• Prolonged prone restraint of a subdued suspect is clearly established as excessive force, regardless of initial resistance, when officers continue applying weight after it is unnecessary.
• The duty to intervene is activated for every officer who is present and has a realistic opportunity to stop excessive force, even when the officer’s own contact is minor or momentary.

2. Summary of the Judgment

The district court denied summary judgment to the defendant officers on (a) excessive-force and (b) failure-to-intervene claims. On interlocutory appeal the defendants argued they were entitled to qualified immunity. Judge McHugh, writing for a unanimous panel (Hartz, McHugh, Moritz JJ), affirmed. Although the panel found the district court’s fact section incomplete, it conducted an independent “cumbersome review” of the record, supplied the missing facts in the light most favorable to plaintiffs, and held:

1. Removal of Mr Krueger by his hair, head-slamming him and later tasing him in “drive-stun” mode after he was effectively subdued violated the Fourth Amendment and was clearly established as unconstitutional (citing Davis, Perea, Booker).
2. Keeping 600+ lbs. of officer weight on a hand-cuffed, shackled, non-struggling suspect for about four minutes constituted excessive force clearly established by Weigel, Booker and subsequent cases.
3. Every defendant who observed but failed to stop either episode could be liable for failure to intervene, a principle clearly established at least since Fogarty and Booker.

3. Analysis

3.1 Precedents Cited and Their Influence

• Graham v. Connor (1989) – Provided the three-factor objective-reasonableness test (severity, threat, resistance). The panel emphasised evaluating all phases of an encounter, not just its onset.
• Weigel v. Broad (10th Cir. 2008) – Found prone-restraint pressure for three minutes after restraint unnecessary. Krueger relies heavily on Weigel to define the “clearly established” nature of prone-restraint danger.
• Estate of Booker v. Gomez (10th Cir. 2014) – Establishes that pressure on back of restrained inmate + taser misuse = excessive force; also clarifies group liability and failure-to-intervene. Krueger extends Booker to roadside arrests.
• Perea v. Baca (10th Cir. 2016) – Ten taser cycles on a misdemeanant held excessive. Referenced for the rule that continued tasering of a subdued suspect is unlawful.
• Davis v. Clifford (10th Cir. 2016) – Hair-pull extraction of misdemeanant from vehicle. Used to show the officers were on notice that violently pulling a low-level offender from a car is disproportionate.
• Fogarty v. Gallegos (10th Cir. 2008) – Articulates failure-to-intervene liability without separate pleading. Krueger re-invokes this procedural point.

3.2 Court’s Legal Reasoning

1. Scope of Appellate Jurisdiction – Although typically limited on interlocutory review, the court employed three doctrines (“cumbersome review,” “blatant contradiction,” and “legal-error” exceptions) to re-examine the factual record de novo because the district court’s fact-finding was incomplete, partially inaccurate, and based on faulty legal standards.
2. Two-Step Qualified-Immunity Inquiry
   a) Constitutional Violation: – Initial head-slam and hair-pull failed all three Graham factors (minor offence, no weapon, no time to comply). – Prolonged prone restraint violated factors two & three once threat dissipated. b) Clearly Established: the above precedents placed every defendant on notice, negating qualified immunity.
3. Group & Individual Liability – Drawing on Booker, the panel okayed factual aggregation for officers acting in concert, yet still examined each defendant’s acts (or omissions) to confirm personal participation or conscious non-intervention.
4. Failure-to-Intervene Doctrine – Re-affirmed that an officer present at the scene who observes excessive force and has a “realistic opportunity” to stop it, but does nothing, breaches a clearly established duty, even if that officer’s own hands-on force was minimal or nonexistent.
5. Causation & Medical Evidence – The court accepted the estate’s expert opinion linking positional asphyxia and broken ribs to weight-bearing restraint, underscoring that a jury could find causation without expert unanimity.

3.3 Potential Impact

• Operational Policies: Agencies will likely revise field-training modules to emphasise the danger of any prolonged prone restraint and the immediate obligation to reposition suspects once hand-cuffed.
• Body-Worn Camera Protocols: The panel’s emphasis on missing or incomplete video (and adverse inference possibilities) may prompt stricter policies and disciplinary rules on continuous recording.
• Litigation Strategy: Plaintiffs can cite Krueger to defeat qualified-immunity motions where officers apply force beyond the point of control, or where any officer silently observes.
• District-Court Practice: Judges are reminded (Booker footnote revived) to explicitly list the facts assumed for summary-judgment analysis; omissions now risk a Tenth-Circuit-led “cumbersome review.”
• Training on Duty to Intervene: Krueger extends clear-establishment notice to every officer, including late-arrivers and those with “brief contact,” removing ambiguity agencies sometimes invoke.

4. Complex Concepts Simplified

• Qualified Immunity: A legal shield protecting officials from suit unless (i) they violated a constitutional right and (ii) that right was “clearly established” at the time. “Clearly established” means existing precedent has placed the unlawfulness of the conduct beyond debate.
• Prone Restraint / Positional Asphyxia: When a person is held face-down (prone) with body weight on the back. This compresses the chest, impeding breathing and can quickly lead to oxygen deprivation and cardiac arrest.
• Drive-Stun Mode: A taser setting in which electrodes contact skin directly, causing intense pain but limited neuromuscular incapacitation. It is supposed to be brief and used only when strictly necessary.
• Failure-to-Intervene: Liability concept holding officers accountable for inaction. If an officer witnesses a colleague’s unlawful force and has time and means to stop it yet does nothing, the bystander officer commits a constitutional violation.
• Cumbersome Review of the Record: On interlocutory appeal the circuit court may comb through videos, depositions and exhibits itself to determine the facts “a reasonable jury could find,” when the district judge’s recital is deficient.

5. Conclusion

Krueger v. Phillips underscores that the constitutional calculus does not freeze at the moment an officer first encounters resistance; it evolves as soon as resistance ceases or control is achieved. Continuing a high-risk prone restraint or re-deploying pain-compliance tools after control is gained crosses the clearly established line into excessive force. Equally, every officer at the scene must either stop the unlawful force or share in the liability. In fortifying these principles – and by insisting on meticulous factual analysis at the summary-judgment stage – the Tenth Circuit delivers a stern reminder: constitutional reasonableness is measured not only by what officers do, but also by what they fail to undo.