Probable Cause as a Dispositive Pleading Barrier in § 1983 Wrongful-Prosecution Suits; Fourteenth Amendment Fabrication Claims Require Nonconclusory Causation Allegations

1. Introduction

Morphew v. Chaffee County, Colorado (10th Cir. Apr. 6, 2026) arises from the State of Colorado’s 2021 arrest and prosecution of Barry Morphew for the first-degree murder of his wife, Suzanne Morphew, who disappeared in May 2020. On the eve of trial, the defense discovered prosecutors had withheld exculpatory material. The State dismissed the case without prejudice in April 2022.

Mr. Morphew then filed a sweeping civil action under 42 U.S.C. § 1983 (and a Colorado analog) against prosecutors, law-enforcement officials, and municipal entities. He alleged, among other things, malicious prosecution, fabrication of evidence, Franks v. Delaware warrant-affidavit violations, conspiracy, failure to intervene, reckless investigation (substantive due process), and Monell v. Department of Social Services municipal liability. The district court dismissed the federal claims under Rule 12(b)(6), chiefly because the complaint did not plausibly plead an absence of probable cause. The Tenth Circuit affirmed.

The core appellate issues were pleading-stage: (i) how courts evaluate probable cause when the complaint attaches and repeatedly references the arrest affidavit, (ii) whether multiple § 1983 theories can be dismissed together where probable cause is adequately shown, and (iii) what must be pleaded to connect alleged fabricated evidence (and investigative “recklessness”) to the plaintiff’s deprivation of liberty.

2. Summary of the Opinion

The Tenth Circuit held that most of Mr. Morphew’s federal claims fail at the threshold because his complaint—considered alongside the attached arrest affidavit—does not plausibly allege he was arrested and prosecuted without probable cause.

The court further held that even though a Fourteenth Amendment fabrication-of-evidence theory is not necessarily defeated by the existence of independent probable cause, Mr. Morphew still did not state such a claim because he pleaded only conclusory assertions of causation and did not plausibly allege that the supposed fabrications caused (i.e., proximately led to) his arrest/prosecution in light of abundant uncontested inculpatory information in the affidavit.

Finally, assuming (without deciding) that a substantive due process “reckless investigation” claim exists for pre-arrest conduct, Mr. Morphew did not plausibly plead causation and thus did not state the claim.

3. Analysis

3.1 Precedents Cited

A. Pleading standards and what materials may be considered at Rule 12(b)(6)

  • Bell Atl. Corp. v. Twombly and Ashcroft v. Iqbal: The court reaffirmed that plausibility requires factual content, not “labels and conclusions,” and that courts disregard conclusory assertions. This supported rejecting generalized “proximate result” and “directly resulted” allegations as insufficient.
  • Clinton v. Sec. Benefit Life Ins. Co., Cuervo v. Sorenson, Matney v. Barrick Gold of N. Am., Kansas Penn Gaming, LLC v. Collins, Brooks v. Mentor Worldwide LLC, and Bledsoe v. Carreno: Used to articulate the Tenth Circuit’s contemporary plausibility framework—eliminating conclusory allegations and refusing allegations contradicted by properly considered documents.
  • Brown v. City of Tulsa, Waller v. City & Cnty. of Denver, and Gee v. Pacheco: Emphasized the “four corners” rule and its limited exceptions. Critically, the court relied on the exception for documents attached to the complaint and central to the claims—here, the arrest affidavit—allowing a probable cause assessment at the pleading stage.

B. Probable cause: definition, role, and when it can dispose of multiple claims

  • Kaley v. United States: Reinforced that probable cause “is not a high bar,” supporting dismissal even where the investigation appears “wrongful” in other respects.
  • United States v. Johnson and Wolford v. Lasater: Anchored the court’s statement that probable cause is “more than a bare suspicion but less than a preponderance,” requiring a “substantial probability.”
  • Erikson v. Pawnee Cnty. Bd. of Cnty. Comm'rs: Used to demand “specific facts” showing lack of probable cause; conclusory assertions cannot survive dismissal.
  • Bruner v. Baker: Cited for the proposition that probable cause can go to a jury if “room for a difference of opinion” exists; the court held no such room existed on these pleadings given the affidavit’s undisputed inculpatory facts.
  • Kerns v. Bader: Supported the idea that probable cause can serve as a unifying and efficient ground to resolve multiple Fourth-Amendment-adjacent claims.
  • Out-of-circuit persuasive support: Brown v. City of Albion (6th Cir. 2025) was cited to underscore that dismissal is proper when allegations fail to plausibly suggest the absence of probable cause.

C. Malicious prosecution and the Fourth Amendment foundation

  • Fenn v. City of Truth or Consequences and Pierce v. Gilchrist: Confirmed that lack of probable cause is an element of § 1983 malicious prosecution in this circuit.
  • Becker v. Kroll and Taylor v. Meacham: Reiterated that the Fourth Amendment supplies the constitutional basis for pretrial malicious prosecution claims.
  • Mondragon v. Thompson and Myers v. Koopman: Used to foreclose Mr. Morphew’s attempt to ground malicious prosecution in the Fourteenth Amendment, because Colorado provides an adequate state remedy.

D. Franks-type claims: materiality framed through a “corrected affidavit”

  • Franks v. Delaware: The governing standard—false statements or omissions violate the Fourth Amendment when they are material to probable cause.
  • Kapinski v. City of Albuquerque, United States v. Herrera, and United States v. Perez: Reinforced the “but for” materiality concept and the court’s authority to apply the correct legal framework when the issue is properly presented (including rejecting the “party presentation” objection to the court’s own probable-cause synthesis).

E. Fabrication of evidence: Fourth Amendment vs Fourteenth Amendment theories

  • Manuel v. City of Joliet: Provided the Fourth Amendment baseline: pretrial detention is unconstitutional absent probable cause. This supported the court’s conclusion that a Fourth Amendment fabrication theory fails if independent probable cause exists.
  • Warnick v. Cooley: Recognized fabrication can violate Fourth Amendment rights, but also helped frame that fabrication must have a constitutionally relevant “use” or “harm.”
  • Truman v. Orem City: Central to the due process fabrication claim. The court treated Truman’s causation requirement as dispositive: the plaintiff must plausibly allege a causal connection between fabrication and deprivation of liberty.
  • Buckley v. Fitzsimmons (Scalia, J., concurring): Quoted via Warnick for the proposition that mere preparation of false evidence is not itself a constitutional violation absent harmful use.
  • Martinez v. Carson: Used to underscore proximate-cause principles in § 1983—liability tracks harms proximately caused by defendant conduct.
  • The opinion also canvassed persuasive authority distinguishing Fourth- and Fourteenth-Amendment fabrication theories, including Barnes v. City of New York, Spencer v. Peters, Harris v. Town of S. Pines, Halsey v. Pfeiffer, Zambrano v. City of Joliet, Dean v. Phatak, Tanner v. Walters, Weiland v. Palm Beach Cnty. Sheriff's Off., Limone v. Condon, and the contrary-leaning Riddle v. Riepe. The Tenth Circuit did not adopt a new global test from these cases; it used them to clarify that due process fabrication is not automatically defeated by probable cause, yet still demands plausible causation.

F. Conspiracy, failure to intervene, and Monell: derivative structure

  • Dixon v. City of Lawton and Snell v. Tunnell: Established that a § 1983 conspiracy requires an actual deprivation of rights; without an underlying constitutional violation, conspiracy fails.
  • Bledsoe v. Carreno, Jones v. Norton, and Harper v. Albert: Supported the principle that failure-to-intervene requires a predicate constitutional violation.
  • Monell v. Department of Social Services, Collins v. City of Harker Heights, and Lucas v. Turn Key Health Clinics, LLC: Reinforced the elements of municipal liability and the need for an underlying constitutional tort.
  • Hinkle v. Beckham Cnty. Bd. of Cnty. Comm'rs: Provided a direct analogy: Monell claims fail where probable cause exists (no underlying false arrest/constitutional tort).

G. “Reckless investigation” and substantive due process constraints

  • Romero v. Fay: Recognized, at least in principle, substantive due process concerns for an “unreasonable post-arrest investigation,” which the court contrasted with Mr. Morphew’s pre-arrest theory.
  • Barham v. Town of Greybull: Noted uncertainty about a constitutional right to a reasonable post-arrest investigation.
  • Parker v. City of Tulsa: Cited for skepticism (in an unprecedential decision) about a standalone reckless-investigation claim, especially for pre-arrest conduct.
  • Becker v. Kroll, Tonkovich v. Kansas Bd. of Regents, Uhlrig v. Harder: Used to emphasize the narrowness of substantive due process claims and their demanding causation/culpability requirements.

H. Supplemental jurisdiction and other procedural points

  • United States v. Botefuhr: Supported dismissal of supplemental state claims once federal claims are dismissed before trial.
  • Nevada v. Hicks: Cited to note immunity defenses are not jurisdictional, so the court could affirm on merits without addressing immunity.
  • United States v. Esparza-Mendoza: Used to decline addressing unnecessary issues given affirmance.
  • Markley v. U.S. Bank Nat'l Ass'n and State v. U.S. EPA: Addressed (and rejected) the party-presentation argument; courts remain responsible for applying governing law when issues are properly presented.
  • Bruce v. City & Cnty. of Denver: Supported judicial notice of the later 2025 state indictment (rendering related motions moot).

3.2 Legal Reasoning

A. The “corrected affidavit” approach at the pleading stage

A central move in the opinion is methodological: because Mr. Morphew attached the arrest affidavit and made it “central” to his claims, the court treated it as properly considered on a Rule 12(b)(6) motion under Brown v. City of Tulsa. The district court then performed the functional equivalent of a Franks-style “corrected affidavit” review—accounting for alleged exculpatory omissions and stripping alleged falsehoods—while still recognizing “hundreds” of undisputed inculpatory facts.

The Tenth Circuit endorsed that approach and held that, even as corrected in plaintiff-favorable fashion, the affidavit still established probable cause. The court stressed the “low bar” of probable cause under Kaley v. United States and framed the question as whether a “substantial probability” existed that Mr. Morphew committed the crime, not whether the prosecution could prove guilt beyond a reasonable doubt.

B. Probable cause as the dispositive deficiency across multiple causes of action

The court treated probable cause as the “chief” pleading deficiency for: malicious prosecution (where lack of probable cause is an element), Fourth Amendment fabrication (where detention without probable cause is the injury), Franks violations (materiality is “but for” probable cause), and derivative theories (conspiracy, failure to intervene, and Monell) because each requires an underlying constitutional violation.

A noteworthy aspect is how the court rejected the argument that probable cause is always a “jury issue.” It acknowledged Bruner v. Baker but held that the pleadings and incorporated affidavit left “no room for debate” on probable cause, making dismissal appropriate.

C. Due process fabrication: not “probable cause,” but “plausible causation”

The opinion’s most concrete doctrinal clarification comes in its treatment of Fourteenth Amendment fabrication. Drawing on Truman v. Orem City, the court held that even if probable cause does not categorically defeat a due process fabrication claim, the claim still fails unless the plaintiff plausibly pleads that the fabricated evidence was used in a way that caused the deprivation of liberty.

Here, the court found Mr. Morphew’s pleading problem was not simply that he alleged fabrication, but that he did not allege nonconclusory facts showing the fabricated evidence mattered—i.e., that the charging decision would not have occurred, or would have been materially different, without it. Given the “abundance” of uncontested inculpatory information, generic assertions that fabrication “resulted directly” in detention were treated as the kind of conclusory causation statements rejected by Iqbal and Khalik v. United Air Lines.

D. “Reckless investigation”: skepticism plus causation failure

The panel did not recognize a new pre-arrest reckless-investigation cause of action. It emphasized the narrowness of substantive due process under Becker v. Kroll and noted Romero v. Fay concerned “post-arrest” investigation. But even assuming such a theory might exist, it held the complaint still failed for lack of plausible causation—again rejecting conclusory “proximate result” statements as insufficient.

3.3 Impact

  • Early dismissal in high-profile wrongful-prosecution suits becomes more likely where the warrant or arrest affidavit is incorporated. By treating the attached affidavit as central and properly considered under Brown v. City of Tulsa, the court signals that plaintiffs who plead around probable cause must do so with particularity, anticipating a corrected-affidavit analysis at the motion-to-dismiss stage.
  • Probable cause operates as a “gatekeeping” pleading issue across many § 1983 theories. Even where claims have different elements, the court approved using probable cause as common ground to dispose of claims whose constitutional injury presupposes a lack of probable cause or requires an underlying violation (e.g., conspiracy, failure to intervene, Monell).
  • Fourteenth Amendment fabrication claims require a concrete causation narrative. The decision places practical pressure on plaintiffs to plead: what evidence was fabricated, how it was used, who used it, and why it made a difference to charging, detention, or continuation of proceedings—especially where other inculpatory facts exist.
  • Substantive due process “reckless investigation” theories remain precarious in the Tenth Circuit. The opinion reinforces the circuit’s reluctance to constitutionalize investigative quality pre-arrest, and it indicates causation pleading will be a major hurdle even if the theory is assumed available.

4. Complex Concepts Simplified

  • Probable cause: A relatively low evidentiary threshold—more than suspicion, less than “more likely than not.” The question is whether there is a substantial probability the suspect committed the crime, not whether the government can prove guilt at trial.
  • Rule 12(b)(6) plausibility: The court accepts well-pleaded facts as true, but not legal conclusions. If the complaint and properly considered documents show the claim is not plausibly supported, dismissal is permitted before discovery.
  • Franks v. Delaware claim: Challenges warrants obtained using knowingly/recklessly false statements or material omissions. The court asks whether a “corrected” affidavit would still establish probable cause. If yes, there is no constitutional violation.
  • Fourth vs. Fourteenth Amendment fabrication: Under the Fourth Amendment, the injury is detention without probable cause—so independent probable cause defeats the claim. Under the Fourteenth Amendment, the focus is due process and the fairness of the prosecution; probable cause is not always a complete defense, but the plaintiff must plausibly allege that fabrication was used in a way that caused the deprivation of liberty.
  • Monell liability: Cities/counties are not automatically liable for employees. The plaintiff must show a policy/custom caused a constitutional tort. Without an underlying constitutional violation, the Monell claim fails.
  • Supplemental (pendent) jurisdiction: Federal courts commonly dismiss state-law claims after federal claims are dismissed early, allowing state courts to handle the remainder.

5. Conclusion

Morphew v. Chaffee County, Colorado is a pleading-stage decision that underscores two practical rules in the Tenth Circuit. First, where an arrest affidavit is incorporated into the complaint, courts may evaluate a corrected version of that affidavit at Rule 12(b)(6), and the presence of probable cause will defeat malicious prosecution, Franks-based theories, Fourth Amendment fabrication claims, and derivative claims. Second, even where probable cause is not categorically dispositive—most notably, for a Fourteenth Amendment fabrication-of-evidence theory—the plaintiff must still plead a nonconclusory causal chain showing that fabrication actually drove the deprivation of liberty. The opinion thus reinforces probable cause and causation as the central gatekeeping allegations in wrongful-arrest/wrongful-prosecution civil rights complaints.