Key Takeaway
New York medical malpractice case law on expert testimony requirements, causation standards, and triable issues of fact for summary judgment motions.
This article is part of our ongoing experts coverage, with 80 published articles analyzing experts issues across New York State. Attorney Jason Tenenbaum brings 24+ years of hands-on experience to this analysis, drawing from his work on more than 1,000 appeals, over 100,000 no-fault cases, and recovery of over $100 million for clients throughout Nassau County, Suffolk County, Queens, Brooklyn, Manhattan, and the Bronx. For personalized legal advice about how these principles apply to your specific situation, contact our Long Island office at (516) 750-0595 for a free consultation.
Severino v Weller, 2017 NY Slip Op 01325 (1st Dept. 2017)
This is from the dissent which would have granted summary judgment to the doctor and the hospital. The statement of law is interesting and dare I say useful when looking at healthcare professionals’ affirmation:
“Generally, “the opinion of a qualified expert that a plaintiff’s injuries were caused by a deviation from relevant industry standards would preclude a grant of summary judgment in favor [*5]of the defendants” (Diaz v New York Downtown Hosp., 99 NY2d 542, 544 ). However, a plaintiff’s expert’s opinion “must demonstrate the requisite nexus between the malpractice allegedly committed’ and the harm suffered” (Dallas—Stephenson v Waisman, 39 AD3d 303, 307 ). If “the expert’s ultimate assertions are speculative or unsupported by any evidentiary foundation … the opinion should be given no probative force and is insufficient to withstand summary judgment” (Diaz, 99 NY2d at 544; Giampa v Marvin L. Shelton, M.D., P.C., 67 AD3d 439 ). Further, the plaintiff’s expert must address the specific assertions of the defendant’s expert with respect to negligence and causation (see Foster-Sturrup, 95 AD3d at 728-729). Here, the opinions of plaintiffs’ experts, submitted in opposition to defendants’ prima facie showing that the injury sustained by Mr. Severino was the result of an unpredictable and unpreventable respiratory arrest, were based on supposition and hindsight, and were unsupported by the proof, and were therefore insufficient to raise a material issue of fact (see Manuel H. v Landsberger, 138 AD3d 490 , lv denied 28 NY3d 909 ; Foster-Sturrup, 95 AD3d at 728; Fernandez v Moskowitz, 85 AD3d 566, 568 ; Brown v Bauman, 42 AD3d 390, 392 ).”
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Legal Context
Why This Matters for Your Case
New York law is among the most complex and nuanced in the country, with distinct procedural rules, substantive doctrines, and court systems that differ significantly from other jurisdictions. The Civil Practice Law and Rules (CPLR) governs every stage of civil litigation, from service of process through trial and appeal. The Appellate Division, Appellate Term, and Court of Appeals create a rich and ever-evolving body of case law that practitioners must follow.
Attorney Jason Tenenbaum has practiced across these areas for over 24 years, writing more than 1,000 appellate briefs and publishing over 2,353 legal articles that attorneys and clients rely on for guidance. The analysis in this article reflects real courtroom experience — from motion practice in Civil Court and Supreme Court to oral arguments before the Appellate Division — and a deep understanding of how New York courts actually apply the law in practice.
About This Topic
Expert Testimony in New York Litigation
Expert testimony is essential in most personal injury and no-fault cases — from medical experts establishing causation and damages to accident reconstructionists and economic experts calculating lost earnings. New York courts apply specific rules governing expert qualifications, the foundation for expert opinions, the use of medical journals and treatises, and the sufficiency of expert evidence on summary judgment. These articles analyze the legal standards for expert testimony and practical strategies for presenting and challenging expert evidence.
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How are expert witnesses used in New York personal injury cases?
Expert witnesses provide specialized opinion testimony that helps the court or jury understand complex issues like medical causation, injury severity, future care needs, economic losses, and engineering defects. Under New York law, expert testimony must be based on facts in evidence, the expert's professional knowledge, or a combination of both. The expert must be qualified by training, education, or experience in the relevant field. Expert disclosure requirements under CPLR 3101(d)(1)(i) require parties to identify their experts and provide detailed summaries before trial.
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About the Author
Jason Tenenbaum, Esq.
Jason Tenenbaum is the founding attorney of the Law Office of Jason Tenenbaum, P.C., headquartered at 326 Walt Whitman Road, Suite C, Huntington Station, New York 11746. With over 24 years of experience since founding the firm in 2002, Jason has written more than 1,000 appeals, handled over 100,000 no-fault insurance cases, and recovered over $100 million for clients across Long Island, Nassau County, Suffolk County, Queens, Brooklyn, Manhattan, the Bronx, and Staten Island. He is one of the few attorneys in the state who both writes his own appellate briefs and tries his own cases.
Jason is admitted to practice in New York, New Jersey, Florida, Texas, Georgia, and Michigan state courts, as well as multiple federal courts. His 2,353+ published legal articles analyzing New York case law, procedural developments, and litigation strategy make him one of the most prolific legal commentators in the state. He earned his Juris Doctor from Syracuse University College of Law.
Disclaimer: This article is published by the Law Office of Jason Tenenbaum, P.C. for informational and educational purposes only. It does not constitute legal advice, and no attorney-client relationship is formed by reading this content. The legal principles discussed may not apply to your specific situation, and the law may have changed since this article was last updated.
New York law varies by jurisdiction — court decisions in one Appellate Division department may not be followed in another, and local court rules in Nassau County Supreme Court differ from those in Suffolk County Supreme Court, Kings County Civil Court, or Queens County Supreme Court. The Appellate Division, Second Department (which covers Long Island, Brooklyn, Queens, and Staten Island) and the Appellate Term (which hears appeals from lower courts) each have distinct procedural requirements and precedents that affect litigation strategy.
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