I have reviewed the case referenced above for the purpose of determining whether any criminal laws were violated by the driver involved in this incident.

STANDARD OF CRIMINAL REVIEW

Pursuant to Idaho Code § 18-109, “a crime or public offense is an act committed or omitted in violation of a law forbidding or commanding it, and to which is annexed, [an enumerated] punishment.” Pursuant to Idaho Code §§ 19-505 and 19-506, in order to charge a crime, there must be sufficient facts which tend to establish there is probable cause to believe that an offense has been committed and that the defendant committed it. In other words, there must be both a prohibited act and sufficient evidence to establish probable cause to believe that an individual violated a law, which requires or proscribes an act, and provides for a punishment for committing or omitting the act.

ANALYSIS AND CONCLUSION

Question Presented. Whether the facts developed in the Idaho State Police incident and reconstruction reports support criminal charges under Idaho law against driver Steven L. Guymon arising from a vehicle–pedestrian collision on Interstate 15 that resulted in the death of pedestrian Larry G. Farrar, specifically analyzing potential liability for reckless driving, inattentive/careless driving, speeding/basic speed rule violations, vehicular manslaughter/criminally negligent homicide or DUI.

Reckless driving. A reckless driving charge requires proof of willful or wanton disregard, which is qualitatively more culpable than mere negligence. The present record shows that Guymon was traveling in the left lane at a self‑reported 87 mph in an 80 mph zone, and he diverted his gaze to his mirror as he prepared to return to the right lane. Speed alone, particularly a 7‑mph exceedance on a rural interstate with clear, dry, daylight conditions, typically does not establish willful or wanton disregard without aggravators such as racing, weaving through traffic, severe distraction, or disregard of known hazards.

Here, aggravating factors are limited. The reconstruction’s modeling suggests that even at 80 mph, a collision likely still would have occurred at substantial impact speed, though with more lateral avoidance potential. The reconstruction estimated at 87 mph an impact around 69 mph with insufficient distance to stop, and at 80 mph an impact around 55 mph with increased potential lateral displacement, while underscoring the uncertainty of exact pedestrian position and the risks of swerving at high speed.

On these facts, and in light of a pedestrian unlawfully entering and occupying a high‑speed lane, the evidence of willful or wanton disregard is weak. A factfinder could view the mirror check as ordinary lane‑change behavior rather than reckless distraction, given no sight obstructions, clear conditions, and the sudden presence of a pedestrian. Witnesses behind Guymon could see Farrar crossing; Guymon reported he did not see him until it was too late. Without corroborated excessive speed well above the limit, lane weaving, phone use, or similar factors, reckless driving is presently not strongly supported.

Inattentive/careless driving. Inattentive or careless driving captures sub‑reckless failures of due care. The theory would be that a reasonably prudent driver in the left lane should have maintained forward observation sufficient to detect a pedestrian entering the lane sooner, especially given straight, level, clear‑day conditions and absence of sight obstructions. The contrary consideration is the sudden‑emergency doctrine: the appearance of a pedestrian unlawfully crossing a rural interstate at highway speeds can constitute an unexpected hazard leaving little time to react, particularly when a driver is legitimately checking mirrors preparatory to a lane change. The reconstruction applied an 85th‑percentile total response time of 2.38 seconds and, using 87 mph, found only about 135 feet available for avoidance after perception–reaction, which is less than modeled stopping distance. That modeling relies on the driver’s self‑reported speed and assumed pedestrian starting point and pace. If independent data corroborate those inputs, inattentive driving remains a closer question: a trier of fact could conclude that the combination of speed above the limit and forward observation lapse contributed to the failure to avoid, but could also credit the sudden emergency, given the unusual pedestrian behavior. On balance, inattentive/careless driving is more supportable than reckless driving, contingent on speed corroboration and precision about pedestrian conspicuity and lane position.

Speeding/basic speed rule. The record supports a prima facie case that Guymon exceeded the 80‑mph limit based on his admission. Guymon stated he was traveling 87 mph. Independent corroboration is advisable for charging beyond an infraction, but a straightforward speed infraction is presently supportable on the admission alone if credited. The basic rule theory would posit that, even if not greatly above the limit, traveling at 87 mph while preparing to change lanes reduced available reaction and stopping distance in the face of foreseeable hazards, including unexpected roadway users. The reconstruction’s comparative analysis suggests meaningful differences in remaining distance and impact speed at 80 vs. 87 mph, bearing on causation. At 80 mph, the reconstruction estimated greater lateral avoidance potential and a lower impact speed, while at 87 mph stopping before impact was not feasible given the modeled distances. A basic‑rule charge is supportable but benefits from EDR or other speed corroboration to strengthen proof and causal linkage.

Vehicular manslaughter/criminally negligent homicide concepts. Such charges require proof that the defendant caused death through conduct meeting criminal negligence or recklessness standards, or via specified predicate offenses, depending on the statute. The current record presents significant mitigation: a pedestrian unlawfully and imprudently walking into high‑speed traffic, apparent methamphetamine impairment, and clear roadway conditions. Witnesses observed Farrar casually walking across travel lanes; others earlier described him hunched, staggering, and seemingly unaware on the nearby off‑ramp; hospital testing detected methamphetamine; and a trooper previously encountered Farrar near I‑15 the day before after a report was made of Farrar laying on the ground with his ankle in the travel lane.

The reconstruction acknowledges that even at the posted limit the collision likely would not have been avoidable via straight‑line braking given timing and distances. Modeled stopping distance from 87 mph was about 360 feet, exceeding the roughly 135 feet available after perception–reaction, and swerve feasibility and effectiveness are uncertain at high speed, especially without precise impact location. Without proof of gross deviation—such as materially higher speed, egregious distraction, or other aggravation—criminal negligence or recklessness causing death is not well supported on this record.

Under Idaho law, a vehicular manslaughter charge based solely on driving 87 mph in an 80 mph zone — where speed was not a major factor in the death — faces serious legal obstacles and would likely be very difficult to sustain. Idaho’s vehicular manslaughter statute requires both (1) that the defendant committed an unlawful act with at least ordinary negligence, and (2) that the unlawful driving was a significant cause contributing to the death. When speed is not a major factor in the fatality, the State would struggle to establish the required causal link between the minor speed excess and the death, and a court would likely find the charge legally insufficient.

Idaho’s Vehicular Manslaughter Statute. Idaho Code § 18-4006(3) defines vehicular manslaughter as the unlawful killing of a human being without malice, in which the operation of a motor vehicle is a significant cause contributing to the death because of one of three categories of conduct ID ST § 18-4006:

(a) The commission of an unlawful act, not amounting to a felony, with gross negligence (a felony);

(b) The commission of a violation of Idaho Code §§ 18-8004 or 18-8006 (DUI or aggravated DUI); or

(c) The commission of an unlawful act, not amounting to a felony, without gross negligence (a misdemeanor).

Driving 87 mph in an 80 mph zone is a traffic infraction — an unlawful act not amounting to a felony — and would not constitute a DUI. Accordingly, such conduct could only fall under subsection (a) (felony) or subsection (c) (misdemeanor). The analysis below addresses both.

The Negligence Requirement. Although subsection (c) on its face only requires an “unlawful act,” Idaho courts have consistently held that negligence is a required element of vehicular manslaughter. In State v. McNair, 141 Idaho 263 (2005), the Idaho Court of Appeals held that the State must prove a culpable mental state of at least simple (ordinary) negligence before a defendant can be convicted of misdemeanor vehicular manslaughter under § 18-4006(3)(c). The court reasoned that Idaho Code § 18-4012 (excusable homicide) and § 18-201(3) collectively express a legislative intent that there is no criminal homicide when a death occurs through an accident and entirely without any negligence or other culpable behavior State v. McNair, 141 Idaho 263 (2005). The Idaho Supreme Court confirmed this interpretation in State v. Ochoa, 169 Idaho 903 (2022), holding that misdemeanor vehicular manslaughter requires at least ordinary negligence, and that the State carries the burden to prove the defendant’s unlawful and negligent driving was a significant cause of the victim’s death.

For the felony version under subsection (a), the standard is considerably higher. In State v. Sibley, 138 Idaho 259 (2002), the Idaho Court of Appeals held that gross negligence requires a finding of wanton, flagrant, or reckless disregard of consequences, or willful indifference to the safety or rights of others. Driving 7 mph over the speed limit on an 80 mph highway would almost certainly not meet this elevated standard absent extraordinary circumstances.

Regarding whether a minor speed excess constitutes negligence at all, Idaho law establishes that any violation of the maximum speed limit statute constitutes negligence per se. In Griffith v. Schmidt, 110 Idaho 235 (1985), the Idaho Supreme Court held that violation of Idaho’s maximum speed limit statute is a safety statute violation that constitutes negligence per se, with only causation submitted to the factfinder. Under this rule, even a 7 mph excess speed technically establishes negligence as a matter of law. However, the critical question remains whether this technical negligence was a significant cause of the death — a far more demanding requirement discussed below.

The Causation Requirement: “Significant Cause.” Even though driving 87 mph in an 80 mph zone establishes negligence per se under Idaho law, the most significant obstacle to a vehicular manslaughter charge — when speed was not a major factor in the death — is the causation element. The statute requires that the operation of the motor vehicle be a significant cause contributing to the death. I.C. § 18-4006.

The Idaho Supreme Court addressed this standard directly in State v. Paulson, 169 Idaho 672 (2022), vacating a vehicular manslaughter conviction because the jury was not properly instructed on the required causal link. The Court held that Idaho Code § 18-4006 does not impose strict liability, and that a defendant cannot be convicted of vehicular manslaughter unless the State can prove a causal link between the defendant’s unlawful driving and the death State v. Paulson, 169 Idaho 672 (2022). It is not enough that the defendant was operating a vehicle that was involved in a fatal accident; the unlawful conduct itself must be causally connected to the death.

In State v. Ochoa, 169 Idaho 903 (2022), the Idaho Supreme Court further clarified the “significant cause” standard. The Court noted that the legislature replaced the former “proximate cause” language with “significant cause” in 1983 and 1997, and that this change means the defendant’s driving need not be the only significant cause or the most significant cause of death — it must merely be a significant cause State v. Ochoa, 169 Idaho 903 (2022). However, the Court also acknowledged that determining whether one cause was significant requires an examination of all other potential causes, and that a victim’s own negligence is relevant to the analysis.

When speed was not a major factor in the death, the State faces a fundamental problem: it cannot demonstrate that the 7 mph excess speed was a significant cause of the fatality. If the death resulted primarily from other factors — such as the victim’s own conduct, road conditions, a mechanical failure, or some other cause unrelated to speed — then the causal link between the minor speeding and the death is absent or too attenuated to support the charge. As the Paulson Court emphasized, allowing a conviction without this causal link would improperly transform the vehicular manslaughter statute into a strict liability offense.

DUI. There is no evidence of driver impairment. Reports do not indicate alcohol or drug signs for Guymon, no testing results for him are documented, and he denied needing medical aid while cooperating with troopers. DUI is not supported.

Causation and mental state. Causation in speed/basic‑rule and inattentive theories hinges on whether the excess speed and mirror‑check proximately contributed to the inability to avoid impact. The reconstruction suggests lower impact energy and more lateral avoidance potential at 80 mph, but does not conclusively establish avoidability given unknown precise lane position of the pedestrian and uncertainties about swerve efficacy at highway speeds. The reconstruction explicitly notes the exact location of Farrar in the roadway is unknown and that swerving at 87 mph is unnatural and risky. Mental state evidence for recklessness is minimal; inattentiveness is plausible but contested by sudden‑emergency considerations.

Defenses/mitigation. Sudden emergency is a central mitigation: a pedestrian unlawfully entering an interstate travel lane at highway speeds constitutes an abrupt hazard not of the driver’s making. Investigators concluded Farrar’s conduct violated pedestrian‑on‑highway rules by leaving the shoulder, and multiple witnesses described impairment‑consistent behavior. Contributory fault is not a defense to strict elements but informs proximate cause and culpable mental state assessments for higher charges. The absence of driver impairment, flight, or prior notice of the pedestrian’s position further mitigates.

CONCLUSION/CHARGING ASSESSMENT

On this record, the following charging assessment is recommended: A speed‑related charge is presently the strongest, based on the driver’s admission to 87 mph in an 80 mph zone and the reconstruction’s analysis linking higher speed to reduced avoidance distance and higher impact energy. The posted limit was 80 mph; Guymon reported traveling 87 mph; modeling shows material differences between 80 and 87 mph in available avoidance and impact speed. An inattentive/careless driving charge is mitigated by sudden‑emergency facts, pedestrian unlawfulness, and the brevity and legitimacy of the driver’s mirror glance in a lane‑change context.

Reckless driving is presently not supported for want of aggravating indicators and because the primary hazard was an unlawfully crossing, apparently impaired pedestrian on a rural interstate. Vehicular manslaughter is not supported on the current record absent stronger proof of gross deviation (e.g., materially higher speed, severe distraction) and clearer causation evidence that compliant operation would likely have avoided the fatality. DUI is not supported.

On balance, proceed, if at all, with an appropriate speed/basic‑rule charge. Any higher culpability charging decisions would require new or additional evidence, and are therefore declined for prosecution at this time.