Holdgrafer

In deciding whether a punitive damages award violates the constitutional prohibition of arbitrary or grossly excessive punishment, the most important factor to be considered is the reprehensibility of the defendant’s conduct. The United States Supreme Court has instructed courts undertaking this inquiry that “[a] defendant’s dissimilar acts, independent from the acts upon which liability was premised, may not serve as the basis for punitive damages.” On de novo review, we conclude that evidence of two massive oil spills is too dissimilar to be considered in assessing defendants’ reprehensibility in causing and responding to the underground contamination of plaintiffs’ commercial property. We further conclude that in order to comply with due process, the proscription of “dissimilar acts” evidence in punitive damages cases must apply to both the jury’s predicate determination whether a defendant is liable for punitive damages (Civ. Code, § 3294, subd. (a)), as well as to its subsequent evaluation of a defendant’s reprehensibility in assessing the amount of punitive damages to be awarded.

Unocal Corporation (Unocal) appeals from the judgment awarding $2,564,348 in…