Supreme Court Rules State-Mandated Expert Affidavits Cannot Apply in Federal Malpractice Cases

On January 20, 2026, the United States Supreme Court handed down a unanimous 9-0 decision in Berk v. Choy, resolving one of the most persistent and complicated procedural divides in modern civil litigation. The ruling addressed a highly technical but immensely consequential question: when a medical malpractice lawsuit is filed in federal court, does the plaintiff have to comply with state laws that require an upfront affidavit of merit from a medical expert? Writing for the Court, Justice Amy Coney Barrett delivered a definitive no. The decision immediately alters the landscape of medical liability, stripping away a key early-screening mechanism that healthcare providers have relied upon for decades to dismiss lawsuits at the pleading stage. By prioritizing the uniformity of the Federal Rules of Civil Procedure over state-level tort reform policies, the Court has fundamentally shifted the strategic calculus for both plaintiffs and defendants in malpractice litigation.[1][2]

To understand the gravity of the ruling, one must first understand the state-level hurdles it bypasses. Over the past few decades, 28 U.S. states—including Delaware, New Jersey, Pennsylvania, Illinois, and Missouri—have enacted statutes requiring plaintiffs to file an affidavit of merit or certificate of merit alongside their initial medical malpractice complaint. These laws mandate that a qualified medical expert review the patient's records and swear under oath that the claim has a legitimate medical basis. If a plaintiff fails to attach this document, the state court clerk is often required to reject the complaint outright, or the judge will swiftly dismiss the case before any evidence is exchanged.[2][4]

The legislative intent behind these state statutes is straightforward: tort reform. State lawmakers designed affidavit requirements to act as a rigorous gatekeeper, screening out frivolous or baseless medical malpractice lawsuits before they can inflict financial damage on the healthcare system. Medical litigation is notoriously expensive, and defending a baseless claim through the formal discovery process—which involves depositions, interrogatories, and massive document production—can cost a hospital or physician tens of thousands of dollars. By forcing plaintiffs to secure expert backing on day one, states aimed to protect doctors from the stress and expense of meritless litigation, theoretically stabilizing malpractice insurance premiums in the process.[2][6]

However, the legal mechanics become vastly more complicated when these state-level medical malpractice claims cross into the federal court system. Most malpractice lawsuits are litigated in state courts because patients typically receive care near their homes. But when a patient travels across state lines for medical treatment—for example, a Pennsylvania resident undergoing surgery at a Delaware hospital—the legal dynamics change. If the surgery goes wrong and the patient decides to sue, the fact that the plaintiff and the defendant are citizens of different states allows the plaintiff to file the lawsuit in federal court under a mechanism known as diversity jurisdiction, provided the damages exceed $75,000.[3][6]

Once a state law claim enters a federal courthouse, it triggers a classic constitutional clash governed by the Erie Doctrine. Established by the Supreme Court in 1938, the Erie Doctrine dictates that federal courts sitting in diversity jurisdiction must apply state substantive law (the actual rights and obligations of the parties) but must apply federal procedural law (the rules governing how the lawsuit is conducted). The doctrine was designed to prevent forum shopping and ensure that the outcome of a case does not drastically change simply because it was filed in a federal building rather than a state building across the street.[5][6]

For years, the application of the Erie Doctrine to affidavit-of-merit statutes bewildered the lower courts, creating a sharp and intractable circuit split. The core dilemma was categorization: is an affidavit of merit a substantive protection for healthcare providers, or is it merely a procedural rule dictating what a legal complaint must look like? If it is substantive, federal courts must enforce it. If it is procedural, federal courts must ignore it and rely instead on the Federal Rules of Civil Procedure.[5]

The Federal Rules of Civil Procedure, specifically Rule 8, govern the pleading stage in federal court. Rule 8 intentionally sets a very low bar for entry into the federal justice system, requiring only a short and plain statement of the claim showing that the pleader is entitled to relief. It does not require a plaintiff to attach evidence, expert reports, or sworn affidavits to the initial complaint. The federal system is designed to allow plaintiffs to initiate a lawsuit with basic allegations and then use the formal discovery process to uncover the evidence needed to prove those allegations.[1][4]

Faced with this tension, the federal appellate courts fractured. The Third, Seventh, Eighth, and Tenth Circuits concluded that state affidavit requirements were deeply intertwined with substantive state policies aimed at curbing malpractice costs. These courts ruled that ignoring the state statutes would encourage out-of-state plaintiffs to flock to federal court simply to avoid the expensive upfront burden of hiring a medical expert, thereby violating the core principles of the Erie Doctrine. Consequently, these circuits routinely dismissed federal malpractice claims that lacked the state-mandated affidavits.[1][4]

Conversely, the Second, Fourth, Fifth, Sixth, and Ninth Circuits viewed the issue through a strictly procedural lens. These courts argued that the Federal Rules of Civil Procedure establish a comprehensive and exclusive framework for what must be filed at the pleading stage. Because Rule 8 does not permit states to impose additional front-end evidentiary prerequisites as a condition of proceeding in federal court, these circuits refused to enforce the state affidavit requirements. This deep geographic divide meant that a plaintiff's ability to survive the first day of a federal lawsuit depended entirely on which state the federal courthouse was located in.[1][2]

The Supreme Court finally agreed to resolve the chaos by granting certiorari in Berk v. Choy. The case originated when Harold Berk, a patient, fractured his ankle while visiting Delaware. He subsequently filed a medical malpractice lawsuit in the U.S. District Court for the District of Delaware against Dr. Wilson Choy and the treating hospital, alleging negligent medical care. Crucially, Berk filed his federal complaint without attaching the expert affidavit of merit required by Delaware state law.[2][6]

Relying on established Third Circuit precedent, the federal district court in Delaware dismissed Berk's lawsuit entirely due to the missing affidavit. Berk appealed the decision, but the Third Circuit Court of Appeals affirmed the dismissal, reiterating its stance that Delaware's affidavit requirement was a substantive rule that must be enforced in federal court under the Erie Doctrine. Berk then petitioned the Supreme Court, setting the stage for a definitive national ruling on the intersection of state tort reform and federal civil procedure.[3][6]

In her unanimous opinion reversing the lower courts, Justice Amy Coney Barrett cut through the complex Erie analysis by focusing directly on the text of the Federal Rules. The Court held that Delaware's affidavit-of-merit statute directly conflicts with Federal Rule of Civil Procedure 8. Because Rule 8 prescribes exactly what information a plaintiff must present about the merits of a claim at the outset of a case—merely a short and plain statement—any state law that demands additional evidentiary proof at the pleading stage cannot coexist with the federal standard.[1][4]

The Supreme Court emphasized that the Federal Rules embody a deliberate national choice about access to the federal judiciary. Rule 8 was explicitly drafted to reject the rigid, evidence-heavy pleading requirements of the past, opting instead for a system that allows claims to proceed to discovery based on plausible allegations. By requiring a plaintiff to secure and file expert testimony before discovery even begins, state affidavit laws impose a gatekeeping mechanism that the drafters of the Federal Rules explicitly chose to exclude from federal practice.[4]

During the litigation, the defendants attempted to salvage the state law by offering alternative interpretations. They argued that the Delaware affidavit requirement could be viewed not as a pleading rule, but as a freestanding, early evidentiary screen that federal courts could adopt without violating Rule 8. The Supreme Court firmly rejected this theory, explaining that adopting such a framework would effectively rewrite the state statute. Furthermore, the Court noted that the federal system already has a dedicated mechanism for testing the sufficiency of a plaintiff's evidence: Rule 56, which governs motions for summary judgment after discovery has taken place.[1]

The defendants also tried to rely on Rule 11 of the Federal Rules of Civil Procedure, which governs the ethical certifications made by attorneys when filing documents. Rule 11 contains a specific proviso stating that a pleading need not be verified or accompanied by an affidavit unless a rule or statute specifically states otherwise. However, Justice Barrett's opinion clarified that this language refers exclusively to the verification obligations of the parties and their attorneys, not to substantive evidentiary affidavits provided by third-party medical experts.[1]

The immediate practical effect of the Berk v. Choy decision is a dramatic shift in forum-selection strategy for medical malpractice attorneys. Out-of-state plaintiffs now possess a distinct and powerful advantage: by filing their claims in federal court under diversity jurisdiction, they can entirely bypass the costly and time-consuming process of securing a medical expert before initiating the lawsuit. This lowers the initial financial barrier to entry, allowing plaintiffs to use the federal discovery process to obtain the medical records and depositions necessary to build their case.[5][6]

For healthcare providers and their insurance companies, the ruling represents a significant procedural defeat. Hospitals and physicians in the 28 states with affidavit statutes can no longer rely on federal judges to swiftly dismiss unsupported claims at the pleading stage. Instead, they face the daunting prospect of defending these federal lawsuits through the expensive and protracted discovery phase. Only after discovery is complete will defendants be able to file a motion for summary judgment to challenge the medical validity of the plaintiff's claims, vastly increasing the cost of defense.[1][3]

Legal scholars note that while the decision nullifies affidavit requirements in federal court, it does not invalidate the state laws entirely. State courts will continue to vigorously enforce their own affidavit-of-merit statutes for the vast majority of medical malpractice cases that do not qualify for federal diversity jurisdiction. This creates a bifurcated reality where the procedural hurdles a plaintiff faces are dictated entirely by whether they are suing an in-state or out-of-state doctor, a dynamic that the Erie Doctrine originally sought to minimize.[2][5]

Despite the potential for increased forum shopping, the Supreme Court's ruling serves as a powerful reaffirmation of the supremacy and uniformity of the Federal Rules of Civil Procedure. The decision sends a clear message to lower courts that state legislatures cannot indirectly rewrite federal pleading standards through the guise of substantive tort reform. The federal judiciary retains the exclusive authority to define the rules governing entry into federal court, ensuring that federal practice remains consistent from Delaware to California.[5][7]

Ultimately, Berk v. Choy resolves decades of procedural confusion and provides much-needed clarity to litigants nationwide. While the ruling removes a protective shield for healthcare providers in federal venues, it ensures that the federal courthouse doors remain open to plaintiffs based on the uniform standards established by Congress and the Rules Committee. As the legal community adapts to this new reality, the focus of federal medical malpractice defense will inevitably shift from early pleading challenges to aggressive evidentiary testing during the summary judgment phase.[2][7]