.

Matthew Flanagan

Co-Chair, Disciplinary Board Representation Practice Group

Portrait of Matthew Flanagan

Matt is a highly skilled litigator with over 30 years of trial and appellate experience and serves as Co-Chair of the firm's Disciplinary Board Representation Practice Group. His practice is concentrated on the defense of lawyers against malpractice actions, Judiciary Law 487 claims and grievances. He also defends other professionals and handles general litigation matters on behalf of corporate clients. He has successfully tried cases in New York City and its surrounding counties and has secured dozens of victories in attorney liability cases in New York State’s appellate courts.

With a career-long focus on professional liability litigation, Matt lectures throughout the state on legal malpractice prevention and defense, ethics and professional responsibility. His articles relating to attorney ethics have been cited in the authoritative codification of the laws of New York, as well as New York’s leading treatise on the Rules of Professional Conduct.

Among his numerous professional memberships, he is the past President of the Theodore Roosevelt American Inn of Court and is a member of the New York State Bar Association's Law Practice Management and Insurance Committees. He is a longtime member of the Nassau County Bar Association and served as Chair of the Association’s Ethics Committee from 2019 to 2022. He is also a longtime member of the American Bar Association.

Matt has been recognized annually as a New York Metro Area Super Lawyer for over a decade and is rated AV Preeminent™ by Martindale-Hubbell, the highest peer-review ranking for an attorney's professional and ethical competence. A graduate of St. John's University School of Law and Fordham University, he is admitted to practice before the courts of the State of New York, the United States District Courts for the Southern and Eastern Districts of New York and the United States Court of Appeals for the Second Circuit.

    • St. John's University School of Law (J.D., 1992)
    • Fordham University (B.A., 1989)
    • New York, 1993
    • U.S. District Court Eastern District of New York, 1993
    • U.S. District Court Southern District of New York, 1993
    • U.S. Court of Appeals 2nd Circuit, 1996
    • AV® Preeminent™ by Martindale-Hubbell®
    • New York Metro Area Super Lawyer (2012-2026)
    • American Bar Association (2007-Present)
    • Nassau County Bar Association (1999-present); Ethics Committee (2011-present); Ethics Committee Chairman (2019-2022)
    • New York State Bar Association (1999-present); Law Practice Management & Insurance Committees (2011-present)
    • St. John’s University Alumni Association, Nassau Chapter (2000-present); President (2017-2020)
    • Theodore Roosevelt American Inn of Court, (2011-present); President (October 2023-present)
  • Trends In Claims, Marshall Dennehey Client Presentation, May 5, 2026

    The Art of Mediation, Marshall Dennehey Client Presentation, May 5, 2026

    Attorney Discipline, Theodore Roosevelt American Inn of Court (with program chairs Hon. Randall Eng, Appellate Division, Second Department (ret.), and Hon. Helen Voutsinas, Appellate Division, Second Department), November 15, 2023

    Risk Management and the Rules of Professional Conduct, Nassau County Bar Association, May 12, 2022

    Cybersecurity: Are You and Your Firm Compliant: A Checklist for Lawyers, Joint Presentation of Nassau County Women’s Bar Association and Nassau County Bar Association Ethics Committee, March 3, 2020

    Navigating Malpractice and Ethical Concerns for Trusts and Estates Attorneys, St. John’s University School of Law Continuing Legal Education Weekend, February 8, 2020

    Legal Malpractice: Elements & How to Avoid It, Suffolk Academy of Law, December 12, 2019

    Legal Malpractice: Reducing Your Risk and Strengthening Your Defense, St. John’s University School of Law Spring Continuing Legal Education Weekend, February 10, 2018

    Lawyers’ Ethics: Escrow Accounts (with Hon. Leonard Austin, Appellate Division, Second Department), Theodore Roosevelt American Inn of Court, December 12, 2017
    Judicial Ethics, What’s a Judge to Do? (with Hon. Vito DeStefano and Hon. Randy Sue Marber, Supreme Court, Nassau County), Theodore Roosevelt American Inn of Court, April 27, 2017

    Legal Malpractice: Professional Liability Claims, Litigation Strategies and Attorney Discipline Procedures, New York State Bar Association, Melville, New York, March 31, 2017

    Attorney Ethics: A Discussion of the New Statewide Procedures for Attorney Discipline Matters (with Abraham Krieger, Chairman of Grievance Committee for 10th Judicial District), St. John’s University School of Law Continuing Legal Education Weekend, February 25, 2017

    Legal Malpractice Update, Nassau County Bar Association, February 1, 2017

    • “Escrow Cleanup: Taking Care of the Money Left Behind,” NYSBA Journal, Vol. 90, No. 8, New York State Bar Association, October 2018
    • “On Ethics: Agreements Not To Grieve – Are They Ethical?” – Nassau Lawyer, November 1, 2017 
    • “On Ethics: Addressing Claims Against A Client's Settlement Funds,” Nassau Lawyer, March 1, 2017
    • “Bowing Out Ethically: Ending the Attorney-Client Relationship Before the Matter is Completed,” NYSBA Journal, Vol. 88, No. 7, New York State Bar Association, September 2016
    • "Follow the Money - Escrow Accounts: The Dangers of Excessive Delegation and Deference," NYSBA Journal, Vol. 87, No. 5, New York State Bar Association, June 2015

Results

Summary Judgment Secured for Law Firm

We secured summary judgment for a law firm by successfully arguing that its role in implementing and overseeing a client’s anti-money laundering policies did not encompass the accounting functions the accounting firm had agreed to perform, and that there was no evidence the law firm acted negligently. The underlying malpractice claim was brought by a check cashing company against its accountants, alleging that the accounting firm failed to detect thefts committed by one of the company’s employees. The accounting firm, in turn, filed a third-party contribution claim against the law firm, contending that the firm should have detected the employee’s thefts through its work overseeing the company’s anti-money laundering policies. The Court rejected the accounting firm’s arguments, granted our motion for summary judgment, and dismissed the contribution claim.

Dismissal Secured in New York Legal Malpractice Matter

We secured a decision granting our motion to dismiss an attorney malpractice matter in Orange County, NY. The plaintiff and daughter of the co-defendants sued her parents and our client for breach of contract, breach of fiduciary duty denominated as promissory estoppel, and constructive trust and sought damages of $800,000. The co-defendants allegedly purchased a property for the plaintiff to live and work in and agreed to deed the property to the plaintiff once she paid the mortgage in full. Our client created a family trust naming the plaintiff as trustee, in which the property would be transferred to the plaintiff following the death of both parents. However, following a family dispute, the co-defendants replaced the plaintiff as trustee with our client. Upon the request of the co-defendants and in accordance with the terms of the trust, our client transferred the house to another beneficiary. We filed a motion to dismiss on all counts which the court granted in full.

Thought Leadership

Legal Updates for Lawyers' Professional Liability

Courts in New York Continue to Crack Down on Attorneys’ Faulty Reliance on Generative Artificial Intelligence

July 29, 2026

The latest instance occurred in Landberg v. City of New York, 2026 NY Slip Op 03935, 2026 LX 36495 (2d Dept., June 23, 2026), which was a fairly simple trip and fall case. The plaintiff tripped and fell on a loose brick on a sidewalk and brought an action against the City of New York and the abutting landlord, both of which were awarded summary judgment. The Appellate Division, Second Department, affirmed the grant of summary judgment in a relatively short decision issued in early June.  The court spent far more time later in the month addressing the contents of the brief submitted on behalf of the plaintiff and the conduct of plaintiff’s attorney. In a lengthy decision, the court dissected the plaintiff’s brief, finding that it cited and/or quoted from three cases which did not exist, and then misrepresented the holdings of cases which actually did exist.  One of the fictious quotes purported to be from the court of appeals, but was “directly contrary to what the court of appeals has actually said.” After being confronted with the non-existent cases at the oral argument, the plaintiff’s attorney was offered an opportunity to take a 15-minute recess to come up with an explanation of where the nonexistent cases came from, but he declined the opportunity and said that he had “found them either on Westlaw or Lexis or in a book, a previous case, or another brief.” The court concluded that the attorney was not being candid, and that he should have said (as he later admitted) “that the cases were hallucinated by artificial intelligence.” The court imposed a monetary sanction of $8,000 on the attorney, but the court did not stop there. Although the handling attorney’s actions were contrary to the policies of the law firm he worked for, the firm was sanctioned, too (for $2,500). The attorneys for the defendants, while not sanctioned, were chastised for not alerting the court to the AI hallucinations in plaintiff’s brief.  The court wrote: “Although the attorneys for the owner and the City, who are officers of the court, submitted respondents’ briefs, neither of them alerted this Court about the fabricated citations, fabricated quotations, misstatements of law, and misrepresentations regarding the holdings of real cases contained in the plaintiff’s brief.”   Not surprisingly, the sanction exceeded the sanction which the same court had assessed a few weeks earlier against a pro se litigant. In Matter of Julien v. Arthur, 2026 NY Slip Op 03308, 2026 LX 287806  (2d Dep.t, May 27, 2026), the Second Department sanctioned a pro se litigant in the amount of $250 for his reliance on generative AI. The pro se litigant cited only one nonexistent case, but the court ruled that that was sufficient to warrant the imposition of a sanction. The Julien court noted that the pro se litigant (a father in a custody dispute) acknowledged responsibility for his conduct and that it only occurred once, which undoubtedly factored into the lower monetary sanction. The following month, in distinguishing the much lower sanction awarded in Julien, the Landberg court said: “This case is obviously much more egregious in that the person who filed the subject brief is a trained attorney with access to legal research materials, including Westlaw, and who is bound by the Rules of Professional Conduct.” Attorneys practicing in the Second Department can expect a sanction greater than $250 for even a single AI hallucination or fabricated citation in a brief. The court made it clear in Landberg that attorneys are on notice of the unreliability of generative AI: “stories about the unreliability of GenAI in performing legal work, leading to fictitious citations, misrepresentations of the law, and sanctions, have been widespread in the media for years.”  The court also made it clear that attorneys are expected to alert the court to the AI hallucinations and fabricated cases and quotations in their adversary’s briefs.  The foregoing cases coincide with the New York State Unified Court System’s adoption of a new rule, Part 161, regulating the use of AI. The new rule provides that attorneys cannot be prohibited from using artificial intelligence tools in preparing papers submitted to a court, but the tools must be used “in accordance with the duties and responsibilities that apply to individuals who submit papers to a court.” The rule goes on to suggest that individual judges should adopt a Part Rule which provides: “Every attorney or party who uses an artificial intelligence (AI) tool in preparing any paper submitted to this court is expected to understand that tool's capabilities and limitations. Attorneys and parties need to be aware that AI tools, among other risks and limitations, can generate fabricated information or fictitious citations to authority (commonly known as hallucinations)… Accordingly, any attorney or party who uses an artificial intelligence tool, as defined in 22 NYCRR 161.2(a), in preparing any paper, as defined in 22 NYCRR 161.2(b), filed in or submitted to this court or served on another party in a case before this court is required to carefully review the paper and independently ensure that it contains no fabricated or fictitious cases, statutes, or other material.” Attorneys are on notice of the pitfalls of blind reliance on generative AI and can expect to be sanctioned if they mis-cite or misquote cases in submissions which are prepared with the assistance of AI tools.    

Legal Updates for Lawyers' Professional Liability

California Supreme Court Rejects Automatic Expungement of Attorney Disciplinary Records

January 1, 2026

Last year, we reported on a California State Bar initiative to expunge attorney discipline records, other than disbarment, after eight years. See Legal Updates for Lawyers’ Professional Liability – February 2025. The proposed change was intended to lessen the impact of what was perceived as racial disparities in attorney discipline in California. A 2019 State Bar-commissioned study had found that Black male attorneys in California were more than three times as likely to be placed on probation than white male attorneys. This past October, the California Supreme Court rejected the expungement proposal, without any explanation. The court may have been persuaded by opponents of the measure, many of whom felt that the public is entitled to complete transparency when hiring an attorney. The court may have also been influenced by more recent studies which showed that the racial disparities highlighted in the 2019 study were already narrowing. A study released by the California State Bar in May of 2025 found that while some racial gaps remained, “the discipline system is trending in the right direction.” Whether relied on by the California Supreme Court or not, the report from the 2025 study has some interesting findings which could benefit all attorneys faced with disciplinary complaints. The report suggested that sending letters to encourage attorneys who are subject to disciplinary proceedings to retain counsel may have helped narrow the racial disparities found in the 2019 study. Any attorney facing a disciplinary complaint is well-advised to consult an attorney who is experienced in handing such complaints. Many attorneys are not aware that their lawyers’ professional liability policy likely includes supplemental coverage to pay attorney fees incurred in responding to grievances. The carrier can also help find an attorney to help defend against the grievance should the responding attorney need one. The California Supreme Court’s rejection of the expungement proposal opens the door to the expanded use of the less controversial (and, perhaps, more effective) methods highlighted in the report from the 2025 study, including sending letters to attorneys subject to disciplinary complaints. In addition to encouraging attorneys to retain counsel, the letters could also advise them of the supplemental coverage available under their LPL policies. Legal Update for Lawyers’ Professional Liability – January 2026 is prepared by Marshall Dennehey to provide information on recent legal developments of interest to our readers. This publication is not intended to provide legal advice for a specific situation or to create an attorney-client relationship. We would be pleased to provide such legal assistance as you require on these and other subjects when called upon. ATTORNEY ADVERTISING pursuant to New York RPC 7.1 Copyright © 2026 Marshall Dennehey, all rights reserved. No part of this publication may be reprinted without the express written permission of our firm. For reprints or inquiries, or if you wish to be removed from this mailing list, contact MEDeSatnick@MDWCG.com. 

Firm Highlights

Thought Leadership

Florida Supreme Court Rules Florida Statute §627.70152 Does not Apply Retroactively

In a decision that resolves years of appellate uncertainty and confirms that insurers and insureds alike can rely on the legal framework in place when a policy is issued, the Supreme Court of Florida last week found that Florida Statute §627.70152, which involves an insured’s requirement to provide an insurer with pre-suit notice before filing a suit, cannot be applied retroactively. In Universal Property & Casualty Insurance Company v. Hughes, the Court was presented with the issue of whether the statutory pre-suit notice requirement applied retroactively and whether it would apply to a breach of contract of an insurance policy that was issued before the statute went into effect. Before the Court was an appeal from a homeowner, Ms. Hughes, who sued her insurance carrier, Universal Property & Casualty Insurance Company (Universal) for breach of contract under an insurance policy that was in effect from April 24, 2019 through April 24, 2020. During the policy period, Ms. Hughes suffered a loss and, on May 29, 2019, made a claim for water damage. The carrier investigated the loss and issued payment; Ms. Hughes disputed the payment, finding the amount insufficient for repairs. On July 1, 2021, Florida Statute §627.70152 went into effect, which required insureds to provide notice of intent to initiate litigation against the carrier prior to filing a lawsuit; if an insured filed the lawsuit without complying with §627.70152, a court must dismiss the case without prejudice. On August 4, 2021, Ms. Hughes filed her lawsuit against Universal for breach of contract. Universal moved to dismiss based on her failure to comply with §627.70152. Ms. Hughes contended the notice requirement could not be applied retroactively. The trial court disagreed and dismissed the lawsuit without prejudice, and Ms. Hughes appealed. During the appeal, the Fourth District Court of Appeal, in Cole v. Universal Property & Casualty, 363 So. 3d 1089 (Fla. 4th DCA 2023), ruled that Florida Statute §627.70152 did apply retroactively to policies issued before the effective date of §627.70152. However, the Sixth District Court agreed with Ms. Hughes and overturned the trial court’s ruling, finding the statute could not retroactively apply to policies issued prior to the statute effective date. Thereafter, the other district courts weighed in, with the Third District Court agreeing with the Fourth District Court, and the First, Second and Fifth District Courts agreeing with the Sixth District Court. In resolving the conflict amongst the district courts, the Supreme Court advised “as a general rule, ‘the statute in effect at the time an insurance contract is executed governs substantive issues arising in connection with that contract.’ Hassen v. State Farm Mut. Auto. Ins. Co., 674 So. 2d 106, 108 (Fla. 1996). The Court applied the two-step test when deciding whether a statute has retroactive application: “First, the Court must ascertain whether the Legislature intended for the statute to apply retroactively. Second, if such an intent is clearly expressed, the Court must determine whether retroactive application would violate any constitutional principles.” Menendez v. Progressive Exp. Ins. Co., 35 So. 3d 873, 877 (Fla. 2010). In analyzing the Legislature’s intent, the Court must determine whether the Legislature has manifested a clear command for retroactivity in the statutory text.  In review of the statutory text, the Court found nothing in the language of the statute to indicate that the phrase “all suits” was serving another purpose of expanding its reach to suits based on policies that both predate and postdate the enactment of the statute. Buis v. Universal Prop. & Cas. Ins. Co., 394 So. 3d 738, 741 (Fla. 2d DCA 2024). Further, the Court noted the statute has an effective date, which has long been considered to be evidence against retroactive application of a statute. The Court concluded that, on its face, no provision of §627.70152 speaks to application of the statute to insurance policies issued before the statute’s effective date and therefore, the Legislature did not clearly command retroactivity of the statute to include insurance policies issued prior to the enactment of the statute. The Court briefly reviewed Universal’s argument that the presuit notice requirement was procedural, not substantive, and therefore should be applied retroactively; however, the Court agreed with the Sixth District Court’s finding that, in its entirety, §627.70152 transformed an insured’s ability to sue an insurance company under a property insurance policy and an insurer’s obligations to respond to and pay insurance claims, thus making the requirement a substantive change. The Court thereby upheld the decision of the Sixth District and disapproved the decision of the Fourth District in Cole.

Thought Leadership

Commonwealth Court Reaffirms the Constitutionality of Act 111's IRE Provisions

In this case, the claimant sustained a work injury of January 6, 1994, which was acknowledged by Notice of Compensation Payable (NCP). After the claimant’s receipt of 104 weeks of temporary total disability benefits, the employer filed a Request for an Impairment Rating Examination (IRE). The IRE was performed in May 2023 and the IRE physician found that the claimant had a 5% whole person impairment, under the AMA Guides. The employer filed a Petition based on the IRE results, and the Petition was granted by the WCJ. During litigation, the claimant argued that the IRE provisions of Act 111 (Section 306(a.3) of the Act) were not applicable to her injury, since it predated June 24, 1996, the date Act 57 went into effect, and that the IRE provisions were unconstitutional. The Workers’ Compensation Judge (WCJ)) granted the Petition and the Board affirmed. On appeal to the Commonwealth Court, the claimant argued that Act 111 violated the nondelegation doctrine and that its retroactive application to the claimant’s injury was unconstitutional. The court rejected the arguments on the basis that they had already found the same arguments without merit in multiple, prior cases. The court also addressed an argument made by the claimant that Act 111 was procedurally defective under the Pennsylvania Constitution because it was only considered on two days in each House after having undergone amendments and reassignments. The court noted that the Pennsylvania Constitution requires every bill to be considered on three different days in each House. The claimant maintained that, according to the legislative history, the bill did not receive three separate days of consideration from each House when it was assigned a new bill number. The court pointed out, however, that the bill number, H.B. 1840 remained constant and was considered on three occasions by the House. Further, the court concluded that minor amendments to the bill were germane to its original subject, which was to modify the Act’s IRE process, in accordance with Protz II.

Thought Leadership

The Tolling Trap: Filing Alone Will Not Toll the Statute Without Good-Faith Service

The Eastern District of Pennsylvania recently reinforced a critical limitation on bad faith claims, holding that a timely filing alone will not preserve a cause of action absent a good-faith effort to serve the original process. The plaintiff had presented a claim for underinsured motorist benefits to his auto insurer. The insurer evaluated the claim and determined that the plaintiff’s accident-related damages did not exceed the bodily injury liability insurance limits of the at-fault driver and denied his claim. Among other claims, the plaintiff sought to present a claim for insurance bad faith under 42 Pa. C.S.A. § 8371, to which a two year statute of limitation applies. He first filed a praecipe for writ of summons before the expiration of the statute of limitation. However, the plaintiff did not attempt to serve the praecipe or writ until after the statute of limitations had expired. Additionally, the service failed as the plaintiff had mailed the original process to an incorrect address. Despite receipt of the Postal Service’s failure to deliver the original process, the plaintiff did not attempt to re-serve the writ. Two months later, the plaintiff filed a complaint and then successfully served that complaint. The insurer sought to dismiss the plaintiff’s bad faith claim as time-barred by the statute of limitations. The district court agreed. Though the plaintiff had filed a praecipe for a writ of summons prior to the expiration of the statute of limitations, the statute is only tolled if there is a good faith effort to serve that original process. In this case, the court determined that the plaintiff had failed to perform a “good faith effort to serve the original process”. Additionally, though the filing and service of a complaint can serve as alternative original process when the lawsuit is commenced by the filing of a praecipe for a writ of summons, the plaintiff filed his complaint after the statute of limitations had expired. The plaintiff’s bad faith claim was therefore determined to be barred by the statute of limitations and dismissed by the court, with prejudice. A key takeaway for the defense is not to assume that the statute of limitations has been successfully tolled by a plaintiff merely because a praecipe for a writ of summons or complaint has been filed prior to the expiration of the statute. A filed complaint or writ is only part of the equation. The defense should carefully review the docket and filings to confirm that the plaintiff also performed the requisite good faith effort to serve that original process. A thorough review of the docket may reveal that the plaintiff failed to make the good-faith service efforts necessary to toll the statute of limitations.