Jack is a member of the Professional Liability Department where he concentrates his practice in complex litigation, with emphasis on the defense of professionals, including lawyers, accountants, architects and engineers, insurance brokers, real estate professionals, and directors and officers in matters pertaining to malpractice, negligence, fraud, and defamation. He is also a fellow in the American College of Trial Lawyers, and has tried over 100 cases and argued scores of appeals.
Jack is admitted to practice in New Jersey, the District of New Jersey, the Court of Appeals for the Third Circuit, and the United States Supreme Court. He has also been admitted to try cases in the Commonwealth of Pennsylvania, the Eastern District of Pennsylvania, the Eastern District of New York, and the Southern District of New York, as well as the Supreme Court of the State of New York.
A graduate of the University of Notre Dame Law School, Jack subsequently served as Law Secretary for the Honorable Thomas F. Dalton, J.S.C., Superior Court of New Jersey.
Jack is a frequent speaker for the New Jersey Institute for Continuing Legal Education and the American College of Trial Lawyers on legal malpractice matters.
In 2025, Jack was recognized by the New Jersey Judiciary for his exemplary pro bono work and unwavering commitment to serving the public.
Results
Successful Defense of High‑Profile Condo Board Election Challenge as Court Dismisses Claims With Prejudice
Dismissal Obtained in a Complex Legal Malpractice Case
After four hearings, we obtained the dismissal of a complex legal malpractice action arising out of litigation in the U.S. District Court over the failed purchase of a Kia dealership in New Jersey. The plaintiff’s claims against our client, a well-known transactional lawyer with one of the largest firms in the United States, involved hundreds of thousands of dollars in fees and losses related to the investment in the dealership. Following the hearings, and a re-hearing, we obtained the dismissal because the plaintiff’s expert failed to tie in the damages to the alleged deviations in connection with the handling of the underlying transaction. Following the hearings, the court rejected the expert’s opinion on damages and then granted our application for a dismissal of the entire case.
Thought Leadership
New Jersey Appellate Division Clarifies Limits of Transactional Attorneys’ Duties and Proof of Damages in Legal Malpractice Claims
April 21, 2026
On April 15, 2026, the New Jersey Appellate Division issued an important decision in Gonzalez v. DiBello, et al., A‑2334‑24 (App. Div. Apr. 15, 2026), affirming summary judgment in favor of a transactional attorney accused of legal malpractice and breach of fiduciary duty. Marshall Dennehey’s Jack Slimm and Jeremy Zacharias successfully represented the attorney‑defendant. The decision provides significant guidance to both the malpractice defense bar and transactional practitioners, particularly regarding the scope of an attorney’s duty of care, the role of expert testimony, and the proof required to establish causation and damages. The malpractice action stemmed from an underlying federal lawsuit arising out of a failed transaction to purchase a Kia dealership. An investor alleged that the purchasers and their counsel engaged in a fraudulent scheme, asserting claims including fraud, breach of contract, breach of fiduciary duty, aiding and abetting, and conspiracy. Although the federal complaint named the transactional attorney, the claims against her were dismissed, and she was never found liable. The attorney neither represented the investor nor provided him with legal advice and was unaware that he was the ultimate source of investment funds. Her role was limited to preparing transaction documents required by the manufacturer to reflect a transfer of ownership interests. Following dismissal of the federal action, purchaser Christopher Gonzalez filed a legal malpractice and breach of fiduciary duty action against the attorney. Gonzalez relied on expert reports asserting that the attorney had a duty to investigate the source of funds, determine whether her client was financially capable of consummating the transaction, and uncover any disqualifying relationships among investors. The trial court rejected those opinions, holding that New Jersey law does not impose upon transactional attorneys a duty to investigate the origins of funds passing through a trust account or to assess a client’s financial capacity absent specific circumstances. The Appellate Division affirmed, reiterating that an attorney’s duty in a transaction is “to exercise that degree of reasonable knowledge and skill that lawyers of ordinary ability and skill possess and exercise,” and that alleged violations of the Rules of Professional Conduct do not, standing alone, create a cause of action. The Appellate Division also affirmed dismissal based on the plaintiff’s failure to establish damages and causation through competent expert testimony. Gonzalez sought, among other things, to recover all legal fees incurred defending the federal action and alleged loss of investment. However, his expert offered what the courts deemed a classic “net opinion,” failing to analyze the reasonableness of the fees, allocate which fees were allegedly caused by the claimed malpractice, or quantify any lost benefit of the bargain. The court emphasized that when damages are an essential element of a legal malpractice claim, expert testimony must do more than assert conclusions—it must explain how and why specific damages were proximately caused by the attorney’s conduct. Absent such an analysis, allowing a jury to award all defense fees would impermissibly convert compensatory damages into speculative or liquidated damages. Finally, the Appellate Division rejected Gonzalez’s attempt to salvage his claims through a “suit‑within‑a‑suit” theory or a parallel breach of fiduciary duty claim. Citing Morris Properties, Inc. v. Wheeler, the court reaffirmed that plaintiffs cannot avoid their prima facie proof requirements by invoking trial methodologies, and that expert testimony remains necessary in esoteric malpractice cases. The court further held that Gonzalez could not show he would have recovered in the underlying federal action, particularly where he and the attorney were dismissed from that case. The fiduciary duty claim was properly dismissed as duplicative of the malpractice claim and failed for the same lack of proof on causation and damages. This decision is a significant reaffirmation of rigorous proof standards in transactional malpractice cases and provides meaningful protection against expansive and speculative damages theories.
Legal Updates for Lawyers' Professional Liability
Winning Streak Continues: Major Appellate Decision in DEP-Linked Malpractice Suit
October 31, 2025
Jack and Jeremy received their third successful Appellate Division decision within 30 days in a complex legal malpractice action. Frank Castella v. Gerald Lepis was a major case against an attorney arising out of an environmental claim by the N.J. Department of Environmental Protection, which was litigating against Castella in connection with his purchase of property in Jersey City, New Jersey. The DEP’s claim for the cleanup was in the hundreds of thousands. Dr. Castella alleged that our client failed to give him proper advice and to obtain a Phase 1 Study before he purchased the property. After he purchased the property, the N.J. DEP did a vapor study and found PCE exceeding residential levels. Therefore, they classified it under New Jersey’s Site Remediation Reform Act and its Spill Compensation Control Act (strict liability). The plaintiffs then submitted a claim to the New Jersey Spill Fund, seeking compensation for alleged property value diminution. The DEP issued a denial, referencing the plaintiff’s failure to conduct due diligence before purchasing and stating that the plaintiff was “strictly liable without regard to fault for all clean up and removal costs.” Consequently, the plaintiff filed a complaint for legal malpractice against our client, Mr. Lepis. Castella argued that had he been adequately counselled about the former use of the property by a dry cleaner, he would have taken titles through a corporate entity, obtained an environmental assessment prior to purchase, or declined to proceed with the transaction. Jack and Jeremy submitted discovery requests and obtained orders to which the plaintiff did not respond. He finally responded with an expert report, however the report was deficient. The plaintiff then moved for reinstatement of his complaint, which Jack and Jeremy opposed. The judge gave the plaintiff more time to fix the problem. However, the plaintiff’s expert report was lacking, and the plaintiff’s discovery was also lacking. Accordingly, the court dismissed the case, and the plaintiff moved for reconsideration. That motion was denied. The Appellate Division found that we were prejudiced because we could not mount a defense and could not take depositions without the plaintiff submitting a proper expert report on damages. The plaintiff’s expert report only opined as to the standard of care and deviation. It never went into a monetary figure. In reaching its decision, the Appellate Division followed the case we had argued, which is reported in Morris Properties v. Wheeler, 476 N.J. Super 448 (App. Div. 2023). There, the Appellate Division held that a plaintiff’s failure to present expert evidence on proximate causation and damages in a legal malpractice case entitles defendants through judgment; therefore, the court dismissed the Castella case as a matter of law. In addition, the plaintiff’s expert’s report barely mentioned causation, and it failed to elaborate on causation under Froom v. Perel, 377 N.J. Super 298 (App. Div. 2005). Accordingly, this is a key opinion in legal malpractice actions; it explains the why and how cases can be dismissed even prior to depositions based upon expert reports that do not comply with the strict standards in New Jersey. Legal Update for Lawyers’ Professional Liability – October 31, 2025, 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 © 2025 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 tamontemuro@mdwcg.com.
