## Facts

- Delair drove ahead of McAdoo; both cars traveled in the same direction.
- McAdoo moved into the left lane to pass and drew alongside Delair’s car.
- McAdoo’s left rear tire blew out, his car swerved, and it struck Delair’s vehicle.
- Trial evidence showed McAdoo’s tire was worn through across its surface to the inner lining/fabric, and witnesses described it as visibly worn and dangerous.
- Delair sued for personal injuries and property damage, alleging negligence in operating a car with defective tires.

## Issues

1. Whether operating a vehicle with tires unfit for safe travel is negligent when the defect would be revealed by reasonable inspection.
2. Whether a driver can avoid liability by claiming he did not actually know the tires were dangerously worn.
3. Whether expert testimony is required to prove that a tire worn through to the fabric is unsafe.

## Decision

- The Supreme Court of Pennsylvania affirmed the trial court’s refusal to enter judgment notwithstanding the verdict for McAdoo.
- The evidence permitted the jury to find the tire was unfit for ordinary highway operation and that using it was negligent.
- McAdoo was chargeable with knowledge of the tire’s condition to the extent a reasonable inspection would have disclosed it.
- Expert testimony was not required because the dangerous condition was within ordinary experience and observation.
- The lower court’s separate order granting a new trial due to excessive damages was not before the Supreme Court on this appeal.

## Legal Principles

- An owner-operator must use reasonable care to avoid subjecting others to unreasonable risk from a vehicle’s operation.
- It is negligent to use a defective instrumentality when the user knows or should know the defect creates an unreasonable risk of harm.
- A motorist has a duty to exercise reasonable care in inspecting a vehicle for fitness; the motorist is chargeable with notice of what a reasonable inspection would disclose.
- It is negligence to drive with tires unfit for safe operation when the defect is discoverable by reasonable inspection.
- Expert opinion is unnecessary when jurors can evaluate the condition and its danger using ordinary experience.

## Conclusion

The court held that a driver may be found negligent for a tire blowout caused by an obviously worn tire where reasonable inspection would have revealed the danger, and the jury could assess that danger without expert testimony; accordingly, judgment as a matter of law for the defendant was properly denied.


Delair v. McAdoo, 324 Pa. 392, 188 A. 181 (Pa. 1936)