Probable Cause Required for First Amendment Retaliation Claims Based on Quo Warranto Petitions

I. Introduction

In Jenna Amacher v. City of Tullahoma, Tennessee (6th Cir. June 25, 2026), the Sixth Circuit addressed when a 42 U.S.C. § 1983 First Amendment retaliation claim may proceed where the alleged retaliatory act is the initiation of a quo warranto proceeding seeking to remove an elected official from office.

Parties. Plaintiff-Appellant Jenna Amacher, a Tullahoma alderman, sued the City, its mayor (Ray Knowis), its administrator (Jennifer Moody), and two residents (Scott Van Velsor and Jim Woodard). She alleged that they retaliated against her protected speech by supporting and pursuing a Tennessee quo warranto petition challenging her residency eligibility for office.

Key issues. The appeal primarily presented (1) whether a plaintiff must show absence of probable cause as an element of a First Amendment retaliation claim based on a quo warranto petition, and (2) whether the district court abused its discretion by denying additional discovery time.

II. Summary of the Opinion

The Sixth Circuit affirmed summary judgment for defendants. It held that, in this setting, a First Amendment retaliation claim requires the plaintiff to prove the quo warranto petition lacked probable cause. Because the petition had at least a “probability or substantial chance” of success given Amacher’s prolonged absence from the City and the close factual question of residency intent, probable cause existed and the retaliation claim failed.

The court also affirmed the district court’s management of discovery, finding no abuse of discretion in denying late requests to extend deadlines after ample time had been provided.

III. Analysis

A. The new rule and its doctrinal placement

The opinion extends the Supreme Court’s “no-probable-cause” requirement from retaliatory prosecution and arrest contexts to a retaliatory civil action in the nature of quo warranto—at least where the claim’s closest common-law analog is malicious prosecution/wrongful civil proceedings. In practical terms: if probable cause supported the quo warranto petition, it “does not provide a cognizable basis for a First Amendment retaliation claim in this setting.”

B. Precedents Cited (and how they drive the result)

1) Baseline elements of Sixth Circuit retaliation doctrine

The court began with the circuit’s standard retaliation elements from DeLanis v. Metro. Gov't of Nashville & Davidson Cnty., 160 F.4th 732 (6th Cir. 2025): protected speech, adverse action, and causation. The question here was whether an additional element—absence of probable cause—must be shown when the adverse action is a legal proceeding.

2) Supreme Court retaliation framework: prosecutions and arrests

  • Hartman v. Moore, 547 U.S. 250 (2006): retaliatory prosecution claims require pleading and proving the absence of probable cause, in part because probable cause is powerful circumstantial evidence on causation and because retaliatory-prosecution cases often involve an intermediary decisionmaker (the prosecutor).
  • Nieves v. Bartlett, 587 U.S. 391 (2019): retaliatory arrest claims generally require absence of probable cause, again due to causation difficulties and administrability, subject to a narrow exception where objective evidence shows differential treatment of similarly situated individuals.

These cases supply both the rule (probable cause defeats the retaliation theory) and the rationale (probable cause is a causation proxy and a limiting principle protecting legitimate enforcement/petitioning).

3) Common-law anchoring and “closest analogy” methodology

Relying on Nieves and Heck v. Humphrey, 512 U.S. 477 (1994), the court emphasized that because there was “no common law tort for retaliatory” official acts based on protected speech at the time § 1983 was enacted, courts look to the “closest analogy” in common-law tort.

The court found the closest analog to a retaliatory quo warranto petition is malicious prosecution, because it challenges the wrongful institution of legal process. That choice is reinforced by the plaintiff’s own pleading: she also brought a state malicious prosecution claim based on the same alleged misconduct.

4) Civil-proceedings analogue and “wrongful civil proceedings”

The opinion also invoked the tort of “wrongful civil proceedings” through Pro. Real Est. Invs., Inc. v. Columbia Pictures Indus., Inc., 508 U.S. 49 (1993), which requires the plaintiff to show the challenged lawsuit lacked probable cause. The Eleventh Circuit’s DeMartini v. Town of Gulf Stream, 942 F.3d 1277 (11th Cir. 2019), supplied a closely aligned application of this logic to retaliatory civil litigation, supporting the Sixth Circuit’s extension here.

5) Petitioning immunity and Noerr-Pennington parallels

The court cited Knology, Inc. v. Insight Commc'ns Co., 393 F.3d 656 (6th Cir. 2004), E. R.R. Presidents Conf. v. Noerr Motor Freight, Inc., 365 U.S. 127 (1961), and Pro. Real Est. Invs. to note that Noerr-Pennington-type principles—protecting petitioning activity absent sham litigation—harmonize with a probable-cause screen, and may extend beyond antitrust into § 1983 contexts. The reference to Cox v. Ruckel, No. 23-5698, 2025 WL 2603787 (6th Cir. Sept. 9, 2025), underscored this trajectory within the circuit.

6) First Amendment “shield not sword” and the petition right

The court stressed that citizens have their own First Amendment rights to petition courts, and warned against transforming the First Amendment into a tool for an elected official to punish opponents. It cited Whiting v. City of Athens, 170 F.4th 439 (6th Cir. 2026), and Borough of Duryea v. Guarnieri, 564 U.S. 379 (2011), to frame the importance of protecting petitioning activity.

7) Standards for “probable cause” and its low threshold

On the quantum of proof, the court applied the “probability or substantial chance” conception of probable cause (a “not a high bar” approach), citing Alford v. Deffendoll, 165 F.4th 490 (6th Cir. 2026), Lester v. Roberts, 986 F.3d 599 (6th Cir. 2021), and Kaley v. United States, 571 U.S. 320 (2014).

8) Deliberate reservations and limiting principles

The panel carefully cabined what it did not decide, using existing precedents to mark boundaries:

  • Abuse-of-process type theories: If a plaintiff alleged the proceeding was used to coerce speech/work while lacking any intent to prevail, the analogy might shift to abuse of process, where probable cause is not necessarily a complete defense. See Bickerstaff v. Lucarelli, 830 F.3d 388 (6th Cir. 2016), and Givens v. Mullikin ex rel. Est. of McElwaney, 75 S.W.3d 383 (Tenn. 2002).
  • Selective enforcement exception: The court noted but did not apply Nieves’s similarly-situated evidence exception (objective proof that others not engaged in protected speech were not targeted).
  • Extraordinary “official policy” circumstances: It noted Lozman v. Riviera Beach, 585 U.S. 87 (2018), where probable cause may not bar a retaliation claim if indisputable objective evidence shows an official policy to retaliate.
  • Adverse action uncertainty: The panel explicitly reserved whether a “fair-grounded effort to unseat an elected official” is an adverse action at all, citing Nev. Comm'n on Ethics v. Carrigan, 564 U.S. 117 (2011), and Doe v. Reed, 561 U.S. 186 (2010) (Scalia, J., concurring in the judgment).

C. Legal Reasoning: Why probable cause defeats this claim

The court’s reasoning proceeded in three steps:

  1. Identify the closest common-law analog. A retaliatory quo warranto petition most closely resembles malicious prosecution or wrongful civil proceedings, both requiring lack of probable cause.
  2. Justify the requirement functionally. Probable cause is “highly valuable circumstantial evidence” on causation, especially where a third-party decisionmaker (here, the district attorney) initiates the action and the direct actor may have immunity—paralleling Hartman.
  3. Apply the standard to the facts. Given Amacher’s sale of her in-city home, multi-year out-of-city living, months without any in-city property, and slow construction of a future home, a reasonable litigant could believe a Tennessee court might find she vacated office. The state court itself characterized the question as close—Amacher did “just enough” to show intent to return—supporting the conclusion that the petition had at least “a chance” of success under Pro. Real Est. Invs..

Critically, once probable cause exists, the court held it “makes no difference” if retaliatory motive also existed—consistent with Hartman, Nieves, and DeMartini. The probable-cause requirement operates as a gatekeeping rule: it screens out cases where the challenged legal process was reasonably grounded, thereby protecting legitimate petitioning and reducing speculation about motive and causation.

D. Application to Tennessee’s quo warranto and residency law

The opinion framed the quo warranto petition as a high-stakes civil mechanism to test title to office (“By what right do you hold this position?”) with removal as the remedy. See Tenn. Code § 29-35-116. It also highlighted Tennessee’s residency rule: residency can be maintained if the person intends to return. See Tenn. Code § 2-2-122(a)(4).

That statutory structure made the case fact-intensive (intent to return), and thus inherently one where reasonable parties could disagree—precisely the posture in which a probable-cause screen will often dispose of retaliation claims premised on legal filings.

E. Discovery ruling

Applying Rule 16(b)(4)’s “good cause” standard and deferential review, the court held the district court acted within its discretion in denying further extensions after ~14 months for discovery and one prior extension. The court relied on the district court’s docket-management discretion (citing Taylor v. Bristol-Myers Squibb Co., 93 F.4th 339 (6th Cir. 2024)) and lack-of-diligence principles (citing Inge v. Rock Fin. Corp., 281 F.3d 613 (6th Cir. 2002)).

F. Impact

The decision’s most significant effect is doctrinal: it extends the probable-cause prerequisite to a new category of alleged retaliatory “adverse action”—a quo warranto petition (and, by logic, similar civil proceedings initiating state power to impose serious consequences).

Likely consequences include:

  • Early resolution of retaliation suits challenging reasonably grounded office-eligibility proceedings, often at summary judgment.
  • Greater protection for citizen petitioning to test an officeholder’s legal qualifications, so long as the challenge is not “sham” (i.e., it has probable cause).
  • Strategic reframing incentives: Plaintiffs may try to plead around the rule by emphasizing coercive use of process (abuse-of-process-like facts), invoking Lozman-type official policy evidence, or developing Nieves similarly-situated comparators.
  • Unresolved “adverse action” frontier: The court’s reservation about whether a fair-grounded effort to unseat an official is adverse action leaves future litigants room to contest the claim at an even earlier element.

IV. Complex Concepts Simplified

  • Quo warranto: A legal proceeding asking whether someone is lawfully holding a public office; if not, the remedy can be removal.
  • First Amendment retaliation claim: A claim that government (or those acting under color of law) took harmful action against someone because of protected speech.
  • Probable cause (in this context): Not proof beyond a reasonable doubt; it is a reasonable belief the action had a “chance” of success—often described as a “probability or substantial chance.”
  • Malicious prosecution / wrongful civil proceedings: Common-law torts for wrongfully initiating legal process; historically they require showing the case lacked probable cause.
  • Petition clause / Noerr-Pennington idea: The First Amendment protects the right to ask government bodies—including courts—for relief; liability for petitioning is generally limited to “sham” or baseless proceedings.

V. Conclusion

Amacher establishes a clear Sixth Circuit rule: when a First Amendment retaliation claim is premised on a quo warranto petition (a legal process aimed at removing an officeholder), the plaintiff must prove the petition lacked probable cause. Because the residency challenge here was reasonably grounded—indeed a close call under Tennessee’s intent-based residency doctrine—the claim failed regardless of any alleged retaliatory animus.

The opinion meaningfully strengthens protections for citizen (and official) petitioning to test office qualifications, while leaving open important boundary questions—most notably whether a fair-grounded ouster effort is an “adverse action,” and how exceptions like Nieves comparators and Lozman-type policy evidence might apply in future cases.