In a unanimous decision that surely will recalibrate the balance of power between state gatekeeping statutes and federal pleading standards, the U.S. Supreme Court issued Berk v. Choy, 607 U.S. ___ (2026) on Jan. 20, 2026. There, the court held that Delaware’s “affidavit of merit” requirement for medical malpractice suits is not applicable in federal court because it conflicts with Federal Rule of Civil Procedure 8. Authored by Justice Amy Coney Barrett, the opinion makes one point clear: When a state law demands an evidentiary showing at the filing stage, it crashes headlong into the Federal Rules of Civil Procedure. In arriving at this conclusion, the court was forced to grapple with complex issues related to the Erie doctrine—the well-known principle, famously set forth in Erie Railroad v. Tompkins, 304 U.S. 64 (1938), that federal courts sitting in diversity cases apply state substantive law and federal procedural law.
The dispute in Berk started with Harold Berk falling from his bed. Harold Berk suffered a fractured ankle and was subsequently taken to a Delaware hospital. While fitting him for a protective boot at the hospital, staff allegedly twisted the limb, further injuring it. Despite the trauma, Dr. Wilson Choy declined to order a new X-ray. Two weeks later, a follow-up appointment revealed the ankle was severely deformed.
Berk instituted a diversity action in the U.S. District Court for the District of Delaware, alleging a medical malpractice claim arising under Delaware law. His complaint was dismissed pursuant to a Delaware state law requiring that a medical malpractice plaintiff attach an affidavit of merit, signed by a medical professional, to their complaint. Berk’s failure to do so was fatal to his claim. The U.S. Court of Appeals for the Third Circuit affirmed, holding the Delaware provision was substantive law and, under Erie, had to be applied to dismiss Berk’s complaint in federal court.
The Supreme Court granted certiorari and reversed, but on somewhat unexpected grounds. Rather than wade into Erie’s murky procedural versus substantive dichotomy, the Supreme Court resolved the question by simply holding that the affidavit of merit requirement was in direct conflict with Federal Rule of Civil Procedure 8’s requirement that a complaint need only contain a short and plain statement of the claim. And because Rule 8 regulates procedure and is valid under the Rules Enabling Act, the affidavit of merit requirement could not be thrust upon federal courts. While the decision was unanimous, Justice Jackson concurred because she reasoned the Delaware statute conflicted with Federal Rules of Civil Procedure 3 and 12, not Rule 8.
While the court’s decision is a win for Berk, who need not file an affidavit of merit with his complaint in federal court, the decision and its reasoning have several practical implications for litigators. For one, in the medical malpractice context, plaintiffs unable to secure an affidavit of merit have a new incentive to file in federal court, assuming the other requirements for diversity jurisdiction are met. This will result in increased federal filings in the 28 states that currently have affidavit-of-merit requirements. Conversely, while the defense bar has traditionally sought to remove such cases to the confines of federal court, which are perceived to be more friendly, there is now substantial incentive to remain in state court if an early dismissal can be obtained under state law.
The court’s decision also casts substantial doubt on the applicability of numerous state laws imposing other preconditions to suit. The Supreme Court made it clear—Rule 8 means what it says, that all that is required is a short plain statement of the claim. There are no evidentiary requirements to initiate a lawsuit in federal court. Most obviously, this upends other analogous affidavit-of-merit statutes (limiting suits against accountants, architects, engineers, and lawyers, for example). There is also now a good-faith basis to challenge state exhaustion of remedies requirements, anti-SLAPP statutes, and presentment requirements by arguing that these provisions also conflict with Federal Rules of Civil Procedure 8 and 12. These provisions are routinely used to obtain early dismissal in federal court, but litigants can no longer assume they justify a Rule 12(b)(6) motion. At the very least, parties defending in federal court must be prepared to explain why, unlike an affidavit-of-merit provision, these various preconditions to suit do not conflict with the Supreme Court’s broad reading of Rule 8.
Finally, by rooting its analysis in the plain text of Rule 8 rather than engaging in the more complicated assessment of whether the affidavit-of-merit requirement is procedural or substantive, the Supreme Court opened the door to a more aggressive assertion of federal supremacy in the context of Erie. Federal courts traditionally applied Erie in a manner that sought to avoid finding conflicts between state law and the Federal Rules. But the court’s textualist approach to the interpretation of the Federal Rules suggests this truism no longer rings quite as true. Applying this more expansive view of the Federal Rules could lead to divergent interpretations of state law, depending on the forum. Berk’s ramifications are sure to be wide-reaching, as plaintiffs and defendants must now weigh its impact when deciding whether to file in or remove a case to federal court.
Reprinted with permission from the February 11, 2026 edition of the Delaware Business Court Insider © 2026 ALM Global Properties, LLC. All rights reserved. Further duplication without permission is prohibited, contact 877-256-2472 or asset-and-logo-licensing@alm.com.