## Facts

- David M. Webber, Holly Bray, and Brandy L. Sobba spent time together drinking on August 22, 1997.
- Later that day, Sobba drove Bray’s vehicle on a rural road in Fulton County, Arkansas, with Webber as a passenger.
- The vehicle left the roadway and struck a bridge abutment, seriously injuring Webber, Bray, and Sobba.
- Webber sued Sobba in federal court under diversity jurisdiction, alleging Sobba’s negligent driving caused his injuries.
- Sobba denied liability and asserted defenses including comparative fault and joint enterprise, contending any negligence by her should be imputed to Webber because they were engaged in a joint enterprise.

## Issues

1. Whether Arkansas law permits a driver to assert a joint-enterprise defense (imputed negligence) against an injured passenger in an action between alleged members of the same enterprise.
2. Whether instructing the jury on joint enterprise, over objection, was prejudicial error requiring a new trial when the jury returned a general verdict.

## Decision

- The Eighth Circuit reversed the defense judgment and remanded for a new trial.
- The court held that Arkansas law, as predicted by the federal appellate court, would not allow the joint-enterprise defense to bar or limit recovery in an action by a passenger against the driver.
- The court held the joint-enterprise jury instruction was erroneous and not harmless because the jury returned a general verdict, making it impossible to determine whether the verdict rested on the improper theory.

## Legal Principles

- In diversity cases, federal courts apply state substantive law and, when state law is unsettled, predict how the state’s highest court would rule.
- Under the predicted Arkansas rule, joint-enterprise imputed negligence does not apply in an intra-vehicle negligence suit by one alleged participant (passenger) against another (driver); fault should be assessed based on each party’s own conduct under comparative fault principles.
- When a jury receives an instruction presenting an invalid legal theory and returns a general verdict, reversal is required if the reviewing court cannot conclude the error was harmless.

## Conclusion

The court ordered a new trial because it concluded Arkansas would reject using joint enterprise to impute a driver’s negligence to an injured passenger in a suit between them, and the improper joint-enterprise instruction could have been the basis for the general defense verdict.


Webber v. Sobba, 322 F.3d 1032 (8th Cir. 2003)