Motorized Vehicles Are Per Se “Deadly Weapons” Under Wyo. Stat. § 6-1-104(a)(iv); No “Serious Bodily Injury” Instruction Required

1. Introduction

This appeal arose from a driveway confrontation in Evanston, Wyoming. Susanne Jacqueline Mayeux (“Mayeux”) was convicted after jury trial of (1) felony aggravated assault and battery and (2) misdemeanor interference with a peace officer. The aggravated assault conviction rested on the State’s theory that Mayeux knowingly caused “bodily injury” to Jami Brackin by backing a Tesla into her and pushing her down a sloped driveway. The interference conviction stemmed from Mayeux’s repeated refusal to provide officers her driver’s license, registration, and proof of insurance during the officers’ investigation of the incident.

The appeal presented three issues: (i) whether the jury should have been instructed on the statutory definition of “serious bodily injury,” (ii) whether evidence was sufficient to support the aggravated assault conviction—particularly the “deadly weapon” element, and (iii) whether evidence was sufficient to support the interference conviction.

2. Summary of the Opinion

The Wyoming Supreme Court affirmed both convictions. It held the district court correctly refused Mayeux’s proposed instruction defining “serious bodily injury,” although the district court’s stated rationale misread the “deadly weapon” definition. Relying on Dike v. State, the Court clarified that the “reasonably capable” clause in § 6-1-104(a)(iv) does not apply to enumerated items like “motorized vehicle.”

On sufficiency, the Court concluded that because a motorized vehicle is a deadly weapon by definition, the State only needed to prove Mayeux knowingly caused “bodily injury,” which includes physical pain, bruising/temporary disfigurement, or impairment. For interference, the Court held that refusing to provide required driving documents can “hinder” or “delay” officers and thus constitutes interference even if officers can obtain some information through dispatch or third parties.

3. Analysis

3.1 Precedents Cited

A. Jury instructions and standards of review

• Schnitker v. State and Luedtke v. State (quoting Giles v. State) supplied the general framework: trial courts have “wide latitude” in instructing juries; refusal of a proposed instruction is typically reviewed for abuse of discretion so long as instructions correctly state the law and cover the issues.
• The Court nonetheless treated the pivotal dispute as statutory interpretation—reviewed de novo—citing Bernal-Molina v. State, Blevins v. State, and In Int. of JB for the plain-meaning, “give effect to every word” approach.

B. The “deadly weapon” definition and the last-antecedent rule

• Dike v. State is the opinion’s centerpiece. There, the defendant argued an unloaded firearm was not a “deadly weapon” because it was not “reasonably capable” of causing death or serious bodily injury. The Court rejected that argument by applying a grammatical “last antecedent” principle: the qualifying phrase “which in the manner it is used...” modifies only the final catchall phrase—“other device, instrument, material or substance”—not the earlier enumerated items such as “a firearm.” The same reasoning controls for “motorized vehicle.”
• The Court reinforced Dike through legislative-acquiescence doctrine, citing Marfil v. State (quoting Robert L. Kroenlein Tr. ex rel. Alden v. Kirchhefer): when the Court interprets a statute and the legislature makes no material change, legislative acquiescence is presumed. Because § 6-1-104(a)(iv) was not amended post-Dike, Dike remains controlling.
• The Court cited Moschetti v. Liquor Licensing Authority of City of Boulder (as quoted in Dike) to explain the underlying grammar canon: where a qualifying clause follows a series and is closely connected to the last antecedent—especially after an “or”—it ordinarily modifies only that last antecedent absent contrary legislative intent.

C. Vehicle cases referenced and limited

• Carey v. State was discussed because it contained language suggesting a motor vehicle must be used in a manner “reasonably capable” of causing death/serious bodily injury to qualify as a deadly weapon. The Court expressly undercut its force, noting Carey predated Dike and is not controlling to the extent it conflicts with Dike.
• Urbigkit v. State, abrogated on other grounds by TJS v. State, was distinguished as turning on sufficiency of evidence across theories (attempt/knowing injury/threat) rather than the definitional question whether a vehicle is a deadly weapon.

D. Sufficiency of evidence standard

• Thunder v. State (quoting Ogden v. State) supplied the familiar sufficiency lens: view the evidence in the light most favorable to the State, disregard conflicting defense-favorable evidence, and do not reweigh credibility.

E. Interference with a peace officer doctrine

• For elements, the Court cited Walter v. State (citing Saldana v. State) to list what the State must prove under Wyo. Stat. Ann. § 6-5-204(a).
• For “lawful performance” review, the Court cited Woods v. State (de novo review of legality of officers’ actions).
• On traffic-stop authority, the Court analogized to Hanson v. State (quoting Harris v. State) for the proposition that officers may request license/insurance/registration as part of routine traffic stop/investigation tasks.
• On breadth of interference, the Court relied on Garza v. State (quoting Newton v. State) and Tillett v. State. These cases establish that the statute is “purposefully broad,” can reach conduct “not otherwise unlawful,” and does not require force; “interfere” includes checking, hampering, delaying, or tending to prevent an officer’s performance.
• On overlap and charging discretion, the Court cited McArtor v. State, DeLeon v. State, and Derksen v. State for the propositions that multiple statutes may cover the same conduct and prosecutors generally may choose among them absent improper motive or constitutional violation.

3.2 Legal Reasoning

A. Why “serious bodily injury” did not need to be defined for the jury

Mayeux’s proposed instruction assumed that, to decide whether the Tesla was a “deadly weapon,” the jury needed to decide whether the Tesla was used in a manner “reasonably capable” of producing “death or serious bodily injury.” The Supreme Court held the premise was wrong because, under Dike v. State, the “reasonably capable” clause does not modify enumerated “deadly weapons,” including “motorized vehicle.” As a result, the jury did not need the definition of “serious bodily injury” to decide the “deadly weapon” element: the Tesla qualified as a deadly weapon as a matter of statutory definition.

The Court also endorsed the district court’s practical concern about jury confusion: introducing “serious bodily injury” risked conflating it with the required “bodily injury” element of Wyo. Stat. Ann. § 6-2-502(a)(ii), inadvertently elevating the State’s burden. Importantly, while the district court reached the correct result, it did so after misinterpreting the statute; the Supreme Court corrected the interpretation but affirmed the refusal of the instruction because the instruction was legally unnecessary.

B. Sufficiency for aggravated assault and battery: “deadly weapon” and “bodily injury”

Mayeux’s sufficiency challenge again hinged on the mistaken idea that a motorized vehicle must be used in a “reasonably capable” manner to be a deadly weapon. Once the Court clarified the statutory construction, her argument collapsed: the Tesla was a deadly weapon by definition under Wyo. Stat. Ann. § 6-1-104(a)(iv). The remaining question was whether there was evidence of “bodily injury,” defined broadly in § 6-1-104(a)(i) to include physical pain, bruising/temporary disfigurement, or impairment. Testimony that the Tesla struck Brackin, caused pain, bruising, and a “tweak”/misalignment in her hip, was sufficient for a reasonable jury to find the elements beyond a reasonable doubt.

C. Interference conviction: lawful duties and “interference” by refusal to produce documents

The Court separated two concepts: whether the officers were acting lawfully, and whether Mayeux’s conduct hampered their duties. It rejected the framing that the case involved a demand to “identify herself” or answer questions; the record showed the officers requested driver’s license, registration, and proof of insurance. Mayeux conceded she was statutorily obligated to provide these items (e.g., § 31-2-204(a), § 31-7-116), and the Court found the requests were lawful as part of investigating a “traffic incident”/possible crime.

On “interference,” the Court applied the intentionally broad construction from Garza v. State, Newton v. State, and Tillett v. State: interference includes conduct that hinders, delays, or tends to prevent officers from performing duties, even if passive and even if alternative investigative routes exist. The refusal forced officers to take extra steps: running plates, confirming driver identity through a witness, requesting emailed license information, later locating the driver’s photograph independently, and never confirming insurance. The jury could reasonably find that this “checked or hampered” the investigation, satisfying § 6-5-204(a).

Finally, the Court rejected the “bootstrapping” argument (that failure-to-produce statutes should cap punishment). Citing McArtor v. State, DeLeon v. State, and Derksen v. State, it held overlapping statutory coverage is common and charging choices are within prosecutorial discretion absent unconstitutional motives or violations.

3.3 Impact

A. Clarification with real consequences: vehicles as per se deadly weapons

The opinion’s most significant effect is its explicit application of Dike v. State to “motorized vehicle” in § 6-1-104(a)(iv). In practical terms, prosecutors need not litigate speed, trajectory, or “capability” to establish the “deadly weapon” element when the instrumentality is a motorized vehicle; that element becomes categorical. Defense strategies that previously sought to contest “deadly weapon” by emphasizing slow speeds or minimal injury will now more naturally shift to disputing mental state (intent/knowledge), causation, or “bodily injury.”

B. Jury-instruction practice

Trial courts are given a clearer roadmap: where the deadly weapon is an enumerated item, defining “serious bodily injury” to help the jury assess “deadly weapon” is unnecessary and may confuse. This reduces instruction litigation in aggravated assault cases involving vehicles (and, by parity of reasoning, other enumerated items such as firearms).

C. Interference doctrine: refusal-to-produce as actionable interference

On interference, the decision reinforces that “interference” is not limited to physical obstruction or deception. A refusal to provide lawfully requested documents can constitute interference if it causes investigative delay or hampers access to relevant information. This may lead to more interference charges in situations where individuals decline to produce required documents—even when officers can obtain partial information electronically.

4. Complex Concepts Simplified

• “Last antecedent” rule: When a sentence lists several things and then adds a qualifying phrase at the end, the qualifier usually applies only to the last item in the list—especially when introduced by “or”—unless the statute clearly says otherwise. Here, that means the “reasonably capable of producing death or serious bodily injury” language applies only to “other device, instrument, material or substance,” not to “motorized vehicle.”
• “Deadly weapon” (Wyoming): Under § 6-1-104(a)(iv), certain things are “deadly weapons” by definition (including “motorized vehicle”). For non-enumerated objects (the “other device/instrument/material/substance” category), the State must show the object was used or intended to be used in a way reasonably capable of causing death or serious bodily injury.
• “Bodily injury” vs. “serious bodily injury”: “Bodily injury” is broad and includes physical pain and bruising. “Serious bodily injury” is a higher threshold (e.g., substantial risk of death, protracted impairment, significant fracture). For aggravated assault under § 6-2-502(a)(ii), the required harm is “bodily injury,” not “serious bodily injury.”
• “Interference” with an officer: Interference includes delaying or hampering officers, even without force or threats. It can include passive refusal to do something the law requires (like producing a driver’s license when lawfully demanded) if that refusal hinders the officer’s duties.
• Sufficiency of evidence review: On appeal, courts do not re-try the case. They ask whether a reasonable jury could find guilt beyond a reasonable doubt when the evidence is viewed in the State’s favor.

5. Conclusion

Susanne Jacqueline Mayeux v. The State of Wyoming cements a consequential statutory-construction point: in Wyoming, a “motorized vehicle” is a “deadly weapon” per se under Wyo. Stat. Ann. § 6-1-104(a)(iv), and the “reasonably capable of producing death or serious bodily injury” clause applies only to the statute’s catchall category, not the enumerated items. That clarification narrows the role of “serious bodily injury” in jury instructions for vehicle-based aggravated assault and battery.

The opinion also reinforces the breadth of § 6-5-204(a): refusal to provide lawfully requested driving documents can constitute “interference” because it delays or hampers an investigation, even if officers can obtain some information through dispatch. Together, the rulings strengthen categorical treatment of enumerated deadly weapons and confirm that “interference” reaches passive conduct that obstructs routine police functions.