Although product liability actions are governed by state tort law, they frequently find their way into federal court on diversity jurisdiction. In such actions, federal law provides the procedural rules and state law provides the rule of decision. Although the distinction between procedure and substance is often clear, it can sometimes be nuanced and unintuitive; for example, statutes of limitations are typically viewed as procedural, whereas statutes of repose are viewed as substantive. In Love v. United States, — F.4th — (7th Cir. 2021), 2021 WL 5119342, the Seventh Circuit Court of Appeals provides another such illustration of this nuanced distinction and further guidance on the subject in the context of the admissibility of expert opinions.
The Plaintiff in Love brought suit under the Federal Tort Claims Act (FTCA), alleging that a nurse employed by the Veterans Administration negligently failed to order additional tests after receiving the results of a urinalysis. Plaintiff alleged that the lack of testing allowed an infection to go undiagnosed and untreated, leading to a heart attack and extended hospitalization.
Defendant sought to rebut those allegations with testimony from a board-certified urologist that additional testing was not required by the appropriate standard of care. Plaintiff objected to that testimony on the grounds that, under applicable Illinois state law, a medical professional can only testify within the scope of his or her specialty. Therefore, Defendant’s expert urologist could not opine on whether a nurse had met the standard of care. However, the district court rejected that argument as untimely because it was not raised prior to the deadline for challenging expert witness testimony under Rule 702 of the Federal Rules of Evidence. The district court went on to rule against Plaintiff in a bench trial.
On appeal, Plaintiff argued that he was not required to meet the deadline for Rule 702 motions because he did not argue that the testimony was inadmissible under federal law; rather, state law prohibited the challenged testimony. Because his claim was brought under the FTCA and he was seeking to hold the United States liable “in the same manner and to the same extent as a private individual under like circumstances,” 28 U.S.C. § 2674, Plaintiff argued that any testimony that would be inadmissible in state court must therefore be inadmissible in federal court as well.
The Seventh Circuit began by reaffirming that the Federal Rules of Evidence govern admissibility in federal actions even if, as in an FTCA case, state law supplies the rule of decision. The court then observed that a state rule cast in procedural form may serve a substantive function. For example, many states have adopted a rule in automobile accident cases that excludes evidence of an injured party’s failure to wear a seat belt. The Seventh Circuit explained that, although the rule is presented as evidentiary, federal courts have applied it because it effectively implements a substantive norm—that is, failure to wear a seat belt does not constitute contributory negligence in states that follow this rule.
In contrast, the Seventh Circuit observed that “[h]ow to prove the standard of care in a medical malpractice case is a matter of evidence.” And nothing in Illinois law suggested to the court that there was “any disguised substantive rule” on how a party may prove that standard. Indeed, the court understood Illinois law on medical malpractice as promoting a singular and simple substantive norm: “medical care conforming with professional standards is not actionable.” The issue of which experts may testify as to that professional standard is a matter of competence, governed by the applicable rules of evidence. In federal court, the Federal Rules of Evidence govern.
Love provides a salient reminder that Rule 702, and not state law, governs the admissibility of expert opinion in all actions in federal court—including those actions that, like an FTCA claim or a product liability action, require the federal court to apply state substantive law. The case also offers a good illustration of the difference between “evidentiary” rules that are truly procedural versus those that go to the substance of the action. When a state law governs what can or must be shown in order to make one’s case, it also governs federal actions applying state law. However, when state law merely governs how one may make that showing, federal courts are to look instead to the Federal Rules of Evidence.