549 U.S. 346 (2007)
Philip Morris USA v. Williams is a landmark punitive damages case that further refines constitutional limits on state tort awards under the Due Process Clause.
Does the Due Process Clause of the Fourteenth Amendment permit a state jury to impose punitive damages to punish a defendant for harm to individuals who are not parties to the litigation, and must states provide procedural safeguards (such as clear jury instructions) to prevent that from occurring?
The Due Process Clause prohibits a jury from basing a punitive damages award, in whole or in part, on its desire to punish a defendant for injury inflicted upon nonparties. While a jury may consider harm (or potential harm) to others in assessing the reprehensibility of the defendant's conduct—the most important BMW/State Farm guidepost—it may not use such evidence to punish for those third-party injuries. States must implement procedures, including appropriate limiting instructions, to ensure jurors do not cross this line.
Reversed and remanded. The refusal to give a requested instruction clarifying that the jury could not punish Philip Morris for harm to nonparties violated due process. Although harm to others may inform the degree of reprehensibility, a punitive award cannot be used to punish for injuries to persons not before the court.
Williams is a cornerstone of modern punitive damages law. It operationalizes due process by demanding trial-level safeguards to prevent juries from meting out punishment for harms to nonparties while still permitting use of such harms to gauge reprehensibility. Practically, it obligates defendants to seek, and trial courts to give, careful limiting instructions and provides a distinct ground for appellate reversal independent of substantive excessiveness review under BMW/State Farm. For law students, the case clarifies the difference between two related but distinct inquiries: (1) what evidence a jury may consider to assess blameworthiness, and (2) what the jury may lawfully punish. It also illustrates the Court's continuing effort to cabin punitive damages through both substantive guideposts and procedural protections. Subsequent state-court proceedings underscored the complexity of implementing these principles, but the Williams rule remains a central due process constraint on punitive awards.