## Facts

- A DAPSCO-owned “gang truck,” driven by William McDonald, Jr., suffered recurring mechanical problems and stalled on March 7, 1990, while traveling uphill on Mississippi Highway 528 near Heidelberg.
- Around 6:30 p.m., as it was getting dark, the truck stalled in and blocked the entire eastbound lane; its engine died and the vehicle’s lights went off.
- The disabled truck was not marked with flares, reflectors, lights, or other warning devices, and evidence indicated DAPSCO trucks were not equipped with statutory warning equipment for breakdowns.
- Sam E. McCormick, driving a pickup truck, collided with the rear of the stalled truck and sustained serious injuries.
- McCormick sued McDonald and DAPSCO for negligence; after McCormick later died of unrelated causes, Mary Thomas (administratrix of his estate) continued the action.
- At trial, the court refused plaintiff’s requested negligence-per-se instructions based on Mississippi statutes governing warning devices for disabled trucks and nighttime operation equipment, and instead gave a more general negligence instruction that added a “reasonable time” concept for removing the truck.
- The jury returned a verdict for defendants; Thomas appealed.

## Issues

1. Whether the trial court erred by refusing jury instructions stating that violation of Miss. Code Ann. §§ 63-7-71 and 63-7-69 could constitute negligence per se if the jury found the statutory predicates satisfied.
2. Whether the trial court’s substitute instruction improperly altered the statutory standard by adding an extra-statutory “reasonable time” concept, thereby obscuring the negligence-per-se theory.

## Decision

- The Supreme Court of Mississippi reversed the defense verdict and remanded for a new trial.
- The court held Thomas was entitled to negligence-per-se instructions tied to Miss. Code Ann. §§ 63-7-71 and 63-7-69 because there was evidence supporting submission of statutory violations to the jury.
- The court held the trial court’s substitute instruction was confusing and improper to the extent it displaced the statutes’ specific duties with a “reasonable time” formulation.
- The instructional error was prejudicial because it prevented the jury from being told the legal effect of a statutory violation central to the plaintiff’s theory.

## Legal Principles

- When a safety statute defines a specific duty, and the plaintiff is within the protected class suffering the type of harm the statute aims to prevent, evidence of a statutory violation warrants a negligence-per-se jury instruction.
- Factual disputes about whether statutory conditions are met (including temporal or environmental conditions) are ordinarily for the jury when supported by record evidence.
- A party is entitled to have the jury instructed on a legally valid theory of the case supported by evidence; a trial court may not replace statutory standards with a materially different, non-statutory formulation that dilutes or obscures the theory.

## Conclusion

The court ordered a new trial because the jury should have been instructed that proven violations of Mississippi’s truck-warning and nighttime equipment statutes could constitute negligence per se, and the trial court’s substituted “reasonable time” instruction improperly displaced the statutes’ mandatory duties.


Thomas v. McDonald, 667 So. 2d 594 (Miss. 1995)