No Requirement for Self‑Defense Unanimity Instructions or Special Verdict Interrogatories Under Wyoming Law

Introduction

In James Franklin Mavigliano v. State of Wyoming, 2025 WY 122 (Wyo. Nov. 6, 2025), the Wyoming Supreme Court held that trial courts are not required to give a special jury instruction demanding a unanimous rejection of self-defense, nor must they include a self-defense interrogatory on the verdict form. When a jury is properly instructed that the State bears the burden to prove the absence of self-defense beyond a reasonable doubt and that any verdict must be unanimous, the lack of a separate self-defense unanimity instruction or special interrogatory does not constitute plain error.

The case clarifies Wyoming law on the use of special unanimity instructions and special interrogatories in criminal trials—particularly in the self-defense context—and reinforces the high bar for plain error, especially where pattern instructions correctly state the law and the defense did not object or request a different form below.

Case Overview

Parties and Court

Appellant: James Franklin Mavigliano (Defendant)
Appellee: State of Wyoming (Plaintiff)
Court: Supreme Court of Wyoming, FENN, J., delivering the opinion
Docket No.: S-25-0072
Decision Date: November 6, 2025

Background Facts

On March 5, 2024, law enforcement and EMS responded to Topper Bob’s Motel in Casper, where Chance Arias was found deceased in Room 20. Mr. Arias exhibited injuries consistent with assault, including petechiae, ligature marks on the neck, and facial trauma. Motel surveillance showed a man and woman entering and exiting Mr. Arias’s room repeatedly between 6:35 p.m. and 9:13 p.m.; when they departed at 9:13 p.m., the man carried a blue duffle bag. Police identified the woman as Amber Cook and soon located both her and the male, later identified as James Franklin Mavigliano.

Upon arrest, Mr. Mavigliano possessed a pipe with methamphetamine residue and the key to Room 20. At a nearby bus stop, officers found a blue duffle bag matching the one seen on surveillance; inside was a broken, bloody lamp. Matching lamp pieces were recovered in the room. The lamp cord impressions corresponded to the ligature marks on Mr. Arias’s neck.

After Miranda warnings, Mr. Mavigliano confessed to killing Mr. Arias, recounting an escalating altercation: he delivered multiple punches, struck Mr. Arias with a lamp, and ultimately strangled him with the lamp cord until Mr. Arias stopped resisting. He acknowledged Mr. Arias did not actually strike him, did not threaten him with death or bodily harm, and did not brandish a weapon.

Procedural Posture

The State charged Mr. Mavigliano with second-degree murder and misdemeanor possession of a controlled substance. At trial (December 2024), the defense admitted the killing but asserted self-defense. The court issued standard instructions on the elements of second-degree murder, including the State’s burden to disprove self-defense beyond a reasonable doubt, and gave a general unanimity instruction. The verdict form had no special self-defense interrogatory. The jury convicted on both counts. The court imposed a sentence of 62 years to life on the murder conviction and time served on the possession count. On appeal, Mr. Mavigliano challenged only the murder conviction, arguing plain error in failing to include a self-defense interrogatory or special unanimity instruction.

Note: The opinion includes a typographical error stating “The State charged Mr. Arias” in ¶7; the context makes clear the charges were against Mr. Mavigliano.

Issue Presented

Did the district court commit plain error by failing to include a self-defense interrogatory on the verdict form or a separate instruction requiring a unanimous finding that the State disproved self-defense beyond a reasonable doubt?

Summary of the Opinion

The Wyoming Supreme Court affirmed. Applying plain error review (because the defense neither objected to the verdict form nor requested a special interrogatory), the Court held:

The record clearly reflected the alleged error (prong 1 of plain error).
However, there is no “clear and unequivocal rule of law” in Wyoming requiring a special self-defense unanimity instruction or a self-defense interrogatory on the verdict form. Wyoming pattern criminal jury instructions contain no such requirement, and the Court has never mandated these tools. Special interrogatories in criminal trials are generally disfavored. Therefore, prong 2 of plain error was not met.
Because prong 2 failed, the Court did not reach prejudice (prong 3).

The Court emphasized that the jury was correctly instructed on self-defense (including the State’s burden to disprove self-defense beyond a reasonable doubt) and on the requirement of a unanimous verdict. That was sufficient under Wyoming law.

Analysis

Precedents Cited and Their Influence

Iverson v. State, 2025 WY 19, ¶ 13, 563 P.3d 496, 499 (Wyo. 2025): Restates Wyoming’s three-prong plain error standard—record clarity, violation of a clear and unequivocal rule of law, and material prejudice. Provides the operative framework here.
Lee v. State, 2024 WY 97, ¶ 12, 555 P.3d 496, 499 (Wyo. 2024) and Kobielusz v. State, 2024 WY 10, ¶ 24, 541 P.3d 1101, 1108 (Wyo. 2024): Reinforce the plain error standard and admonish that material prejudice requires a reasonable probability of a more favorable verdict absent the error.
Hayes v. State, 2024 WY 135, ¶ 18, 560 P.3d 902, 906 (Wyo. 2024) and Ingersoll v. State, 2022 WY 74, ¶ 10, 511 P.3d 480, 484 (Wyo. 2022): Clarify that a “merely arguable” violation does not meet plain error’s second prong; reversal is warranted only if the error is so obvious the court should have corrected it sua sponte.
Dixon v. State, 2019 WY 37, ¶ 27, 438 P.3d 216, 228 (Wyo. 2019): Quoted for the principle that plain error requires an obvious judicial misstep that should have been recognized without prompting.
Mackley v. State, 2021 WY 33, ¶ 17, 481 P.3d 639, 643 (Wyo. 2021): Confirms trial judges have broad discretion to craft instructions that correctly state the law and fairly cover the issues; no special language is mandated absent authority.
Neidlinger v. State, 2021 WY 39, ¶ 43, 482 P.3d 337, 349 (Wyo. 2021): Notes that special interrogatories in criminal cases are controversial and “generally not favored,” echoing federal concerns about pressuring juries.
Ridinger v. State, 2021 WY 4, ¶ 43, 478 P.3d 1160, 1170 (Wyo. 2021): Illustrates that failure on any one plain-error prong ends the analysis.
United States v. Ramirez, 537 F.3d 1075, 1083 (9th Cir. 2008), and United States v. Reed, 147 F.3d 1178, 1180 (9th Cir. 1998): Ramirez approved the use of a “Special Issue Unanimity” instruction (and upheld refusal of a special-verdict interrogatory) under Ninth Circuit practice, while cautioning that special verdicts in criminal trials are generally disfavored. The Wyoming Supreme Court used Ramirez illustratively—not as controlling authority—and refused to read it as creating a requirement for a Wyoming trial court to give either a special unanimity instruction or an interrogatory on self-defense.
W.R.Cr.P. 30(a) (2023) and W.Cr.P.J.I. (2020): Together underscore counsel’s obligation to object or propose alternative instructions, and reveal that Wyoming’s pattern instructions do not include a special self-defense unanimity instruction.

Legal Reasoning

The core of the Court’s reasoning lies in prong two of the plain-error test. To show plain error, an appellant must point to a clear and unequivocal rule of law that was plainly violated. Here, there is no Wyoming authority requiring:

a distinct jury instruction that the jury must unanimously reject self-defense to convict; or
a special interrogatory on the verdict form asking jurors to make a separate, unanimous finding on self-defense.

To the contrary, Wyoming law:

Grants trial courts broad discretion in instructing juries, provided instructions accurately state the law and fairly cover the issues;
Treats special interrogatories in criminal cases as generally disfavored; and
Recognizes that general unanimity instructions, coupled with correct burden-of-proof instructions, are ordinarily sufficient.

The trial court’s instructions here properly:

Informed the jury that the State bore the burden to prove beyond a reasonable doubt that Mr. Mavigliano did not act in self-defense; and
Required any verdict to be unanimous.

Because no Wyoming rule mandates a special self-defense unanimity instruction or verdict interrogatory—and given the general disfavor of special verdicts in criminal cases—the Court held there was no clear and obvious legal error. Having failed on prong two, the appellant’s plain-error claim necessarily failed without reaching prejudice.

Comparative Note: The Ninth Circuit’s “Special Issue Unanimity” Instruction

The appellant cited United States v. Ramirez, where a federal appellate court approved a “Special Issue Unanimity” instruction directing jurors to unanimously reject self-defense to convict. Two points are decisive in Wyoming:

Ramirez does not require a special interrogatory; it upheld a trial court’s refusal to use one and warned that criminal special verdicts are not favored.
Wyoming has not adopted the Ninth Circuit’s model “Special Issue Unanimity” instruction. Wyoming’s pattern instructions suffice so long as they correctly allocate the State’s burden to disprove self-defense and require a unanimous verdict.

Thus, Ramirez supports the permissibility—but not the necessity—of a special unanimity instruction. Wyoming’s decision preserves trial-court discretion while declining to impose a new mandatory instruction regime.

Impact and Practical Implications

For Trial Judges

Discretion is reaffirmed: Judges may, but need not, give special unanimity instructions concerning justifications like self-defense.
General instructions remain adequate: A correct instruction placing the burden on the State to disprove self-defense beyond a reasonable doubt, paired with a standard unanimity instruction, suffices.
Use caution with special interrogatories: They remain “generally not favored” in criminal trials due to risks of jury coercion and erosion of the general verdict’s protections.

For Defense Counsel

Preservation is critical: If a special instruction or verdict interrogatory is desired, request it and object to its omission under W.R.Cr.P. 30(a). Absent preservation, plain-error review will likely doom the claim.
Closing arguments matter: Emphasize that if any juror harbors reasonable doubt about self-defense, the proper verdict is not guilty.
Consider tailored language: While not required, a carefully crafted, non-coercive unanimity clarification may be proposed in complex self-defense cases if there’s a risk of juror confusion.

For Prosecutors

Rely on standard instructions: Correct burden-of-proof and unanimity instructions are sufficient; a special interrogatory is unnecessary and potentially problematic.
Record clarity: Ensure the instructions mirror Wyoming law—that the State must disprove self-defense beyond a reasonable doubt once raised—and avoid language that might shift the burden.

For the Jury Instruction Committee and Rulemakers

No mandate to revise patterns: The Court’s decision signals that current pattern instructions are adequate.
Optional tools: The Committee may consider, but need not adopt, an optional “special issue” unanimity clarification for unusual cases; any such tool should be framed to avoid the pitfalls associated with special verdicts in criminal trials.

Substantive Criminal Law

Self-defense posture preserved: Wyoming continues to treat self-defense as a justification the State must disprove beyond a reasonable doubt once the issue is raised, not as an affirmative defense that the defendant must prove.
No expansion of unanimity doctrine: The decision does not extend “specific unanimity” requirements to defensive theories; general unanimity plus correct burden instructions remain the rule.

Complex Concepts Simplified

Plain Error: An appellate doctrine allowing reversal despite lack of trial objection only if (1) the record clearly shows the error, (2) a clear and unequivocal rule of law was violated in an obvious way, and (3) the error prejudiced a substantial right (reasonable probability of a more favorable verdict without the error).
General vs. Specific Unanimity: General unanimity requires agreement on the verdict (guilty or not guilty). Specific unanimity requires agreement on a particular factual basis or issue (e.g., which act or mental state). Wyoming generally requires only general unanimity unless statute or doctrine dictates otherwise.
Special Interrogatory/Special Verdict: Written questions on particular issues (e.g., “Did the defendant act in self-defense?”) answered by the jury in addition to, or as part of, the verdict. In criminal cases, they are generally disfavored because they can pressure juries or intrude on the general verdict’s protective function.
Self-Defense Instruction: In Wyoming, once self-defense is at issue, the State must prove beyond a reasonable doubt that the defendant did not act in self-defense. If the jury harbors reasonable doubt on self-defense, it must acquit.
Heat of Passion Element: For second-degree murder, Wyoming requires proof that the killing was not done in “sudden heat of passion.” If heat of passion is present, the appropriate offense may be manslaughter. Wyoming’s element instruction in this case expressly included the absence of heat of passion.

Key Takeaways

New Clarification: Wyoming law does not require a special self-defense unanimity instruction or a self-defense interrogatory on the verdict form.
Discretion and Pattern Instructions: Trial courts retain broad discretion; standard pattern instructions on self-defense and unanimity are sufficient when they correctly state the law.
Plain Error’s High Bar: Without a clear, unequivocal legal rule mandating a special instruction or interrogatory, the failure to give one cannot be plain error.
Practice Pointer: To preserve instructional issues for appeal, counsel must request the instruction or object to its omission at trial per W.R.Cr.P. 30(a).
Policy Continuity: The opinion aligns Wyoming with the broader principle that special verdicts/interrogatories in criminal trials are generally disfavored due to their potential to coerce or compartmentalize the jury’s decisional process.

Conclusion

James Franklin Mavigliano v. State cements an important instructional principle in Wyoming criminal practice: a general unanimity instruction, combined with a correct allocation of the State’s burden to disprove self-defense beyond a reasonable doubt, satisfies Wyoming law. The Court declined to import the Ninth Circuit’s “Special Issue Unanimity” approach as a requirement and reaffirmed the traditional skepticism toward special verdict forms in criminal cases. Equally, the decision underscores the stringent nature of plain error review and the imperative of timely objections and tailored requests at trial. The ruling provides clear guidance to trial courts and litigants alike, promoting instructional consistency while preserving judicial discretion.

Appendix: Practical Steps to Preserve Instructional Issues

Submit proposed written instructions, including any requested special clarification on unanimity as to self-defense.
Object on the record to the court’s refusal to give the requested instruction or to the absence of a special interrogatory.
Ensure the record includes the precise language requested and the court’s rulings.
In closing, explain the effect of the State’s burden: if any juror has a reasonable doubt as to self-defense, the verdict must be not guilty.
Request curative or supplemental instructions if juror questions suggest confusion about unanimity and self-defense.