Defending Professional Negligence Claims After Moore: Locking the Plaintiff’s Expert and Winning Causation at Summary Judgment

Aaron M. Barham, Partner | Furman Kornfeld & Brennan LLP

Aaron M. Barham is a partner at Furman Kornfeld & Brennan LLP who concentrates his practice on professional liability and legal malpractice defense. Since joining the firm in 2018, Aaron has represented lawyers, accountants, and other professionals in complex litigation, disciplinary proceedings, and high-exposure claims. His practice spans a broad range of underlying subject matters—including commercial litigation, securities, employment, real estate, insurance coverage, trusts and estates, and medical malpractice—and he regularly advises insurers and insured professionals on risk management, liability exposure, and strategic resolution.

• Education & Credentials

Aaron earned his J.D. from St. John’s University School of Law in 2012, where he was a member of the Moot Court Honor Society and served as Symposium Editor of the Journal of Civil Rights and Economic Development, and his B.A. from the University of Virginia in 2007. He is admitted to practice in New York and before the U.S. District Courts for the Southern and Eastern Districts of New York and the U.S. Court of Appeals for the Second Circuit.

• Recognition & Leadership

Aaron has been recognized by Metro New York Super Lawyers for Professional Liability Defense every year from 2019 through 2026. He is a contributor and editor of the New York State Bar Association’s Legal Malpractice CLE Course Book (2019, 2021, 2023, and 2025 editions), reflecting his standing as an authority in the field.

• Professional Involvement

A frequent CLE presenter and author, Aaron speaks and writes on professional liability, legal ethics, and the use of artificial intelligence in legal practice. His recent presentations include “Law Practice Management for Newly Admitted New York Attorneys” and “Legal Ethics, Judgment, and Accountability: Navigating AI with Diligence, Competence, and Candor” for the National Business Institute, as well as programs on malpractice risk management and ethical considerations in real estate closings. His publications include “Generative AI in the Law Office: Managing the Risks” (NYSBA/USI Affinity) and articles on the Corporate Transparency Act, statutes of limitations in legal malpractice claims, and expert testimony, among others.

• Experience

Aaron defends lawyers, accountants, and other professionals in high-stakes malpractice litigation, disciplinary matters, and insurance coverage disputes across a wide array of underlying subject areas. His practice encompasses lawyers’ and accountants’ professional liability, attorney disciplinary defense, agents and brokers liability, appellate practice, cyber security and privacy, insurance coverage, and general liability litigation. Before joining Furman Kornfeld & Brennan, Aaron practiced at a New York City defense firm representing hospitals and healthcare professionals in complex medical malpractice litigation—experience that broadens his perspective in advising and defending professionals today.

James D. Spithogiannis, Partner | L’Abbate, Balkan, Colavita & Contini, L.L.P.

James D. Spithogiannis is a partner at L’Abbate, Balkan, Colavita & Contini, L.L.P., where he defends lawyers and accountants against professional liability claims. His work falls within the firm’s Attorney Liability and Accounting and Business Professionals practices. He came to professional liability defense after practicing commercial and real estate litigation.

• Education & Credentials

James received his Juris Doctor from Brooklyn Law School in 2010, where he earned a CALI Excellence Award. He also holds a Bachelor of Business Administration from the University of Michigan – Ann Arbor. He is admitted to practice in the State of New York and before the U.S. District Courts for the Southern and Eastern Districts of New York.

• Recognition & Leadership

Every year since 2019, James has been named a Rising Star in the New York Metro Edition of New York Super Lawyers. He was promoted to partner at L’Abbate, Balkan, Colavita & Contini, L.L.P.

• Professional Involvement

James has taught continuing legal education for the New York State Bar Association, co-presenting the program “Starting A Solo Practice In New York 2023” with William T. McCaffery on May 16, 2023.

• Experience

James’s practice centers on the defense of attorneys and accountants in professional liability matters, handled through the firm’s Attorney Liability and Accounting and Business Professionals practices. Before joining the firm, he concentrated on commercial and real estate litigation.

SESSION 1 – Locking the Plaintiff’s Standard-of-Care Expert in Legal Malpractice Defense: Rule 702, Rule 37, and New York State-Court Traps | Aaron M. Barham | 12:00pm – 1:00pm

This session shows how to confine the plaintiff’s standard-of-care expert to the four corners of the expert report in legal malpractice and other professional negligence cases. Attendees will learn how the December 1, 2023 amendment to Federal Rule of Evidence 702 places the burden of proof on the side offering the expert, and how to combine that amendment with Rule 37(c)(1) to exclude opinions that were never disclosed or are poorly supported. The session also covers how New York’s state-court disclosure and admissibility rules create parallel opportunities to lock in and exclude the plaintiff’s expert. Attendees will leave with a deposition framework and a motion sequencing strategy they can apply in both federal and state court.

BREAK | 1:00pm – 1:10pm

SESSION 2 – Winning the Case Within the Case: Causation-Based Summary Judgment in Legal Malpractice Defense | James D. Spithogiannis | 1:10pm – 2:10pm

This session shows defense attorneys how to win legal malpractice cases on causation at the summary judgment stage using the case-within-a-case doctrine. It covers New York’s demanding “but for” causation standard, how to expose gaps and speculation in the plaintiff’s expert causation opinions, and how to use the collectibility doctrine as an independent ground for dismissal. It also explains the meaningful differences in causation rules between litigation and transactional malpractice claims, addresses parallel causation defenses in accountant liability cases, and lays out a concrete motion architecture supported by controlling and persuasive authority through 2024–2025.