Failure to Object to a Magistrate Judge’s Report Waives Appellate Review; Qualified Immunity Applies Absent On‑Point Fourth Amendment Stalking-Probable-Cause Precedent

I. Introduction

Case: Deborah Mulcahey v. Township of Chocolay, Michigan, et al.
Court: United States Court of Appeals for the Sixth Circuit
Date: January 8, 2026 (Not Recommended for Publication)

This appeal arose after a neighbor dispute escalated into a criminal stalking charge. Defendant Elizabeth Hillstrom reported to Township law enforcement that plaintiff Deborah Mulcahey engaged in conduct Hillstrom characterized as stalking—harassment, surveillance, photographing/videoing, and directing third parties to trespass. Township officers obtained an arrest warrant; the charge was later dismissed. Mulcahey then sued Hillstrom, Chocolay Township, and several Township employees under 42 U.S.C. § 1983 and state law.

The key appellate issues were: (1) whether the complaint plausibly alleged lack of probable cause sufficient to overcome qualified immunity for the arresting/investigating officers; (2) whether Mulcahey plausibly pleaded a § 1983 conspiracy; and (3) whether Mulcahey preserved appellate review of claims dismissed after she failed to object to a magistrate judge’s report and recommendation.

II. Summary of the Opinion

The Sixth Circuit affirmed the district court’s dismissal of all federal claims. It held:

Qualified immunity: Mulcahey failed to plausibly allege a lack of probable cause for stalking, and in any event failed to identify clearly established, factually similar precedent that would have put the officers on notice that probable cause was lacking under these circumstances.
§ 1983 conspiracy: The complaint contained conclusory allegations of a shared plan but lacked specific facts showing an agreement, a common objective, and coordinated action.
Preservation/waiver: Mulcahey waived appellate review of dismissals as to the Township and one official by failing to object to the magistrate judge’s recommendation, despite an explicit warning.

The court also noted Mulcahey did not challenge the district court’s refusal to exercise supplemental jurisdiction over state-law claims, leaving those claims outside the federal appeal.

III. Analysis

A. Precedents Cited

1. Pleading stage record: considering referenced public documents

Martinez v. Wayne Cnty., 142 F.4th 828 (6th Cir. 2025): The panel invoked Martinez for two foundational propositions: (i) at the motion-to-dismiss stage, courts accept well-pleaded factual allegations as true; and (ii) qualified immunity can be resolved at Rule 12 when the complaint fails to plausibly allege a constitutional violation or clearly established law.
Bassett v. Nat'l Collegiate Athletic Ass'n, 528 F.3d 426 (6th Cir. 2008): The court relied on Bassett to justify considering police reports and the criminal complaint because they were public records and referenced in the pleading—an important step because those documents supplied the factual context supporting probable cause.
Tillman Transp., LLC v. MI Bus. Inc., 95 F.4th 1057 (6th Cir. 2024): Used to reject Mulcahey’s underdeveloped argument that a separate state-court complaint contained “additional allegations.” The court treated the point as waived where it was asserted only perfunctorily.

2. Fourth Amendment, probable cause, and qualified immunity framing

Sykes v. Anderson, 625 F.3d 294 (6th Cir. 2010): Cited for the proposition that lack of probable cause is a core element of Fourth Amendment false-arrest and malicious-prosecution claims under § 1983.
Barrera v. City of Mount Pleasant, 12 F.4th 617 (6th Cir. 2021): Central to the analysis. Barrera supplied: the probable-cause standard (“prudent person”); the notion that reasonable misinterpretation of state law can negate a Fourth Amendment violation (via Heien); and that an officer’s subjective beliefs are irrelevant to probable cause.
D.C. v. Wesby, 583 U.S. 48 (2018): The Supreme Court’s guidance in Wesby drove the “clearly established” analysis: probable cause is a “low bar,” and clearly established law must not be defined at a high level of generality. The court emphasized Wesby’s requirement of a factually similar case to defeat qualified immunity.
Heien v. North Carolina, 574 U.S. 54 (2014): Incorporated through Barrera to underscore that a reasonable mistake of law by an officer can mean “no violation of the Fourth Amendment in the first place.”
Ouza v. City of Dearborn Heights, 969 F.3d 265 (6th Cir. 2020): Acknowledged for the general proposition that arrests without probable cause violate the Fourth Amendment, but the opinion used Ouza (and Wesby) to stress that generalities do not clearly establish illegality in a specific factual setting.

3. Michigan stalking “legitimate purpose” concept and lack of on-point notice

Nastal v. Henderson & Assocs. Investigations, Inc., 691 N.W.2d 1 (Mich. 2005): Mulcahey offered Nastal to support her “legitimate purpose” theory, but the court distinguished it as involving surveillance by a licensed private investigator—too unlike the neighbor-dispute facts to clearly establish the unlawfulness of the officers’ probable-cause assessment.
Hayford v. Hayford, 760 N.W.2d 503 (Mich. Ct. App. 2008): Also cited by Mulcahey, but treated as factually dissimilar (placing an advertisement containing personal information). The court used this to illustrate the absence of close precedent that would have clearly informed the officers.
Gerics v. Trevino, No. 15-cv-12922, 2019 WL 2448324 (E.D. Mich. June 12, 2019) and Gerics v. Trevino, 974 F.3d 798 (6th Cir. 2020): Mulcahey relied on the district court decision denying immunity, but the Sixth Circuit highlighted that, in the later appeal, it noted the officer “undoubtedly had probable cause to arrest” for stalking—thus undermining Mulcahey’s attempt to use Gerics as supportive authority.

4. Probable cause mechanics: witnesses, hearsay, and duty to investigate further

Criss v. City of Kent, 867 F.2d 259 (6th Cir. 1988): Used to reject the idea that officers must credit a suspect’s exculpatory explanation; officers are “under no obligation” to give credence to the suspect’s story once probable cause exists.
Gardenhire v. Schubert, 205 F.3d 303 (6th Cir. 2000): Cited alongside Sykes for the proposition that “mere allegation” or speculation can be insufficient for probable cause—though the court found Hillstrom’s reports were corroborated and supported by photographic evidence.
United States v. Helton, 314 F.3d 812 (6th Cir. 2003): Cited to confirm that hearsay may be considered in the probable-cause assessment.
Crockett v. Cumberland Coll., 316 F.3d 571 (6th Cir. 2003): Used for the rule that, once an officer has probable cause, the Fourth Amendment does not impose a further duty to investigate or to solicit rebuttal from the suspect before arrest.

5. Pleading standards and § 1983 conspiracy specificity

Ashcroft v. Iqbal, 556 U.S. 662 (2009) and Bell Atl. Corp. v. Twombly, 550 U.S. 544 (2007): The court applied the plausibility standard: allegations consistent with liability are insufficient without facts permitting a reasonable inference of liability; “bare assertion of conspiracy” fails.
Bazzi v. City of Dearborn, 658 F.3d 598 (6th Cir. 2011): Provided the definition of a § 1983 conspiracy as an agreement to injure another by unlawful action.
Heyne v. Metro. Nashville Pub. Sch., 655 F.3d 556 (6th Cir. 2011): Supplied the elements (single plan, shared objective, overt act causing injury) and an analogy for insufficiency where allegations show only that defendants “conferred” at points without a pleaded plan.
Bickerstaff v. Lucarelli, 830 F.3d 388 (6th Cir. 2016): Reinforced that conspiracy claims require specificity; vague and conclusory allegations unsupported by material facts do not suffice under § 1983.

6. Appellate preservation: waiver by failure to object to a report and recommendation

United States v. Wandahsega, 924 F.3d 868 (6th Cir. 2019): The decisive authority on waiver: when a party does not object to a magistrate judge’s report (after warning), appellate review of the adopted recommendation is waived.
Souter v. Jones, 395 F.3d 577 (6th Cir. 2005): Mulcahey invoked Souter, but the court distinguished it: Souter preserves appeal for “secondary issues” resolved against an overall prevailing party. Here, the magistrate recommended dismissing entire claims and parties—primary issues—so failure to object waived review.

B. Legal Reasoning

1. Qualified immunity and probable cause for stalking

The opinion follows the now-standard two-path qualified-immunity framework described in Martinez v. Wayne Cnty.: the claim fails if either (i) no plausible constitutional violation is alleged or (ii) the right was not clearly established.

On the “violation” prong, the court emphasized the information allegedly available to police: Hillstrom reported repeated harassment and surveillance-related conduct (pacing at the property line, taking photos/videos, spying) and alleged that Mulcahey directed others to trespass. The complaint and incorporated public documents reflected that Hillstrom offered photographic evidence and that other neighbors corroborated at least some allegations. Against that record, the court applied the low threshold for probable cause described in D.C. v. Wesby. Even if some allegations could be disputed, the court found Mulcahey did not plausibly plead that the officers lacked a reasonable basis to believe stalking occurred under Michigan’s definition of “course of conduct” and “harassment.”

On the “clearly established” prong, the court made Wesby dispositive: it is not enough to cite the general rule that arrests require probable cause; Mulcahey needed a case where an officer in materially similar circumstances was held to violate the Fourth Amendment. Her “legitimate purpose” argument under Mich. Comp. Laws § 750.411h(1)(d) lacked on-point, binding authority to put the officers on notice that the exception clearly applied to the conduct at issue. The opinion therefore held that, even if the officers were mistaken about the reach of the state stalking statute, at most it was a reasonable mistake, which—under Heien v. North Carolina as applied in Barrera v. City of Mount Pleasant—does not amount to a Fourth Amendment violation.

2. Rejection of “ignored exculpatory evidence” and “unreliable witness” theories

Mulcahey argued the police relied on “self-serving” statements and ignored exculpatory evidence. The court acknowledged that there are cases where an eyewitness account can be insufficient (citing Ouza v. City of Dearborn Heights) but emphasized the limiting principle: that concern arises where there is an “apparent reason” to doubt the witness’s reliability. The complaint did not plausibly allege such an apparent reason, especially given claimed corroboration and photographic support.

The court rejected specific sub-arguments:

Suspect’s denial/explanation: Under Criss v. City of Kent, officers are not obligated to credit the suspect’s story once probable cause is established.
Speculation vs. supported allegations: While Sykes v. Anderson and Gardenhire v. Schubert caution against arrests grounded in speculation or “mere allegation,” the record here (as incorporated) reflected more than uncorroborated assertions.
Hearsay use: United States v. Helton supports that hearsay can be considered for probable cause.
Duty to investigate further: Under Crockett v. Cumberland Coll., once probable cause exists, officers need not pursue additional investigation before arrest.
Subjective beliefs: Under Barrera, the officer’s state of mind is irrelevant except for the facts known to the officer.

3. Dismissal of the § 1983 conspiracy claim

Applying Ashcroft v. Iqbal and Bell Atl. Corp. v. Twombly, the court required factual content showing plausibility, not speculation. It reiterated that a § 1983 conspiracy requires an agreement and shared objective (Bazzi v. City of Dearborn), and that plaintiffs must plead with “some degree of specificity” rather than broad accusations (Bickerstaff v. Lucarelli).

The court found Mulcahey’s allegations described, at most, parallel conduct or individual motivations (e.g., that various officials viewed her as a “nuisance”), not facts supporting a “single plan” shared among Hillstrom and Township employees as required by Heyne v. Metro. Nashville Pub. Sch. The cited police report statement about “taking a stand” “together” was deemed too vague to plausibly show an agreement to violate constitutional rights.

4. Waiver of appellate review by failure to object

The court enforced the procedural rule that, when a magistrate judge issues a report and recommendation and explicitly warns that failure to object will waive appellate review, a party’s failure to object waives the right to challenge the adopted recommendation on appeal. Relying on United States v. Wandahsega, the panel held Mulcahey could not revive claims against Throenle and the Township because she did not object in the district court.

The attempted reliance on Souter v. Jones failed because the magistrate’s recommendation was not a case of a party “substantially prevailing” with only “secondary issues” resolved against her; the recommendation eliminated claims and parties—core matters that must be preserved by objection.

C. Impact

Although unpublished and “Not Recommended for Publication,” the opinion is instructive in three recurring litigation settings:

Qualified immunity demands fact-specific “clearly established” authority in probable-cause disputes: The decision reinforces Wesby’s insistence on closely analogous precedent, particularly in probable-cause contexts where fact patterns vary widely. Plaintiffs challenging arrests under state stalking/harassment statutes may face dismissal if they cannot point to binding authority applying the statute’s exceptions (such as “legitimate purpose”) in similar circumstances.
Incorporation of public records at Rule 12 can shape probable cause analysis early: By relying on Bassett to consider police reports and charging documents referenced by the complaint, the court signals how defendants can use incorporated public materials to contest “no probable cause” allegations without waiting for summary judgment—so long as the materials are properly considered.
Strict preservation requirements in magistrate-judge practice: The waiver holding underscores that litigants must object to adverse recommendations even if the case is otherwise moving in their favor. Missing the objection window can end appellate review of claims against particular defendants and can functionally finalize the case’s federal posture.

IV. Complex Concepts Simplified

Qualified immunity: A doctrine protecting government officials from damages liability unless the plaintiff shows (1) a constitutional violation and (2) that the unlawfulness was “clearly established” at the time—meaning prior cases made it obvious to a reasonable official in similar circumstances.
Probable cause: Not proof beyond a reasonable doubt. It is a practical, common-sense judgment that there is a “probability” or “substantial chance” a crime occurred (as emphasized in D.C. v. Wesby).
Reasonable mistake of law (Heien principle): If an officer reasonably misunderstands a law’s scope, the stop/arrest may not violate the Fourth Amendment at all (Heien v. North Carolina).
Pleading plausibility (Twombly/Iqbal): A complaint must allege specific facts making liability plausible, not merely possible. Labels, conclusions, and speculative narratives do not suffice.
§ 1983 conspiracy: More than shared hostility or parallel actions. The plaintiff must plead facts suggesting an actual agreement and coordinated steps to violate rights, with an overt act causing injury.
Waiver for failure to object to an R&R: When warned, failing to object means the party generally cannot later appeal those issues; appellate courts treat them as forfeited.
Supplemental jurisdiction: Federal courts may decline to decide state-law claims once federal claims are dismissed; if unchallenged, that discretionary decision typically ends the state claims in federal court.

V. Conclusion

The Sixth Circuit’s decision affirms a stringent, procedure-and-precedent-driven approach to early dismissal in § 1983 litigation. On the merits, it reiterates that probable cause is a low threshold and that qualified immunity often turns on the plaintiff’s ability to point to factually similar, binding cases. On pleading, it reinforces that § 1983 conspiracy claims require particularized allegations of an actual agreement and shared objective—not inference piled on suspicion. And on procedure, it highlights a decisive practical lesson: failure to object to a magistrate judge’s report and recommendation can waive appellate review entirely, even where the unobjected-to recommendation dismisses claims and parties.