.

John H. Osorio

Chair Emeritus, Architectural, Engineering and Construction Defect Litigation Practice Group

JHOsorio@mdwcg.com

Portrait of John H. Osorio

John serves as Chair Emeritus of the Architectural, Engineering & Construction Defect Litigation Practice Group. In this capacity, he oversees a large group of attorneys throughout many of the firm's offices dedicated in the defense of construction professionals.

For over 30 years, John has handled more than 500 matters in the defense of architectural and engineering firms, general contractors, subcontractors, developers, and owners in litigation matters involving personal injury and property damage. The scope of his representation includes construction and design defect matters, breach of contract, delay damage cases, indemnity and coverage, and construction code and safety violation claims.

In addition to John's vast experience in an all matters of construction litigation, he has handled many hundreds of matters involving personal injury, product liability, and catastrophic loss matters. 

John graduated from the University of Montana in 1979 with a Bachelor of Arts in history and political science. He then went on to receive his juris doctor from Southwestern University School of Law in Los Angeles, California.

    • Southwestern University School of Law (J.D., 1984)
    • University of Montana (B.A., 1979)
    • New Jersey, 1985
    • U.S. District Court District of New Jersey, 1985
    • AV® Preeminent™ by Martindale-Hubbell®
      The Martindale Hubbell rated attorney list is issued by Internet Brands, Inc. A description of the selection methodology can be found here. No aspect of this advertisement has been approved by the Supreme Court of New Jersey.
    • The Best Lawyers in America©, Personal Injury Litigation - Defendants (2026)
    • New Jersey Super Lawyer (2005)
      The Super Lawyers list is issued by Thomson Reuters. A description of the selection methodology can be found here. No aspect of this advertisement has been approved by the Supreme Court of New Jersey.
    • American Bar Association
    • Camden County Bar Association
    • Defense Research Institute
    • Gloucester County Bar Association
    • New Jersey Defense Association
    • New Jersey State Bar Association
    • Construction Defect Litigation in New York and New Jersey, Client Webinar, December 2020
    • Construction Defect Conference Architect & Engineers in Construction Defect Claims, Panelist at Perrin
    • Struggles and Successes of the Past 25 Years, Panelist at West Coast Casualty Conference
    • Risk Transfer in Construction Defect Litigation, client seminars 
    • The Professional (Architect & Engineer) Part in Construction Defect Claims, Panelist, 2nd Annual National Construction Defect Conference, November 2016
    • Minimizing Risk and Avoiding Consequences as a Design Professional in the State of New Jersey
    • Defending Roof Collapse Cases
    • Defending Architect and Engineer Malpractice Claims in New Jersey
    • The Applicability of the Economic Loss Doctrine to Design Professional Claims
    • "Additional Insured Status of Design Professionals," Defense Digest, Vol. 4, No. 3, 1998
    • Proceedings of the 42nd Annual Meeting of Invited Attorneys
    • Successfully argued before the Supreme court of New Jersey in defense of a general contractor defending allegations of construction defect brought by a subsequent condominium association owner.  The Supreme Court held that a construction defect lawsuit must be filed within six years from when the building's original or subsequent owner first knew or, through the exercise of reasonable diligence, should have known of the basis for a cause of action. A subsequent owner stands in no better position than a prior owner in calculating the limitations period. If a prior owner knew or reasonably should have known of the basis for a construction defect action, the  limitations period began at that point. If the building's owner knew or reasonably should have known of construction defects at the time of the sale of the property, the purchaser takes title subject to the original owner's right – and any limitation on that right – to file a claim against the architect and contractors. Thus, a subsequent owner will stand in the shoes of a prior owner for statute of limitations purposes.
    • Successfully argued before the Supreme Court of New Jersey on behalf of a major amusement park owner resulting in the seminal Supreme Court decision on the allocation of liability on behalf of the client as against a sovereign entity that was dismissed from the case due to the plaintiff’s failure to add the sovereign as a direct defendant prior to the expiration of the notice provisions of the torts claim act. Based on our representation, the jury would be instructed to allocate liability for the sovereign’s negligence thus offsetting any potential negligence against the client
    • Represented and successfully resolved a $10 million plus claim brought by a railroad company alleging damage to a bridge as the result of a dam removal and stream restoration project. The matter involved the assertion of design deficiency claims involving geotechnical and hydrological investigation and the means and methods of construction implemented by the general contractor. 
    • Represented a large general contractor in over ten construction defect cases involving high rise condominium and apartment complexes brought by condominium associations and owners.  
    • Successfully represented a solar energy contractor in a breach of contract suit involving the installation of solar panels on numerous public schools in the State of Hawaii, islands of O’ahu and Kauai. The matter was tried for over three weeks heard by a three person binding arbitration panel. After the conclusion of our case in chief, the plaintiff accepted a settlement upon client’s terms. 
    • Successfully tried engineering malpractice claim where the demand was $1.3 million by proving client's design was altered and not the proximate cause of community wastewater treatment facility's failure.
    • Successfully settled multi-plaintiff burn and personal injury case by orchestrating a settlement fund with equal contributions by multiple defendants, thus, capping catastrophic exposure and resolving liability among defendants.
    • Successfully settled multimillion dollar claim by high-rise condominium owners by way of mediation.
    • Successfully resolved multi-plaintiff burn case by way of mediation and use of extensive experts to reduce potential liability.
    • Successfully resolved wrongful death construction case and convinced mediator that general contractor client was the least culpable of all defendants.
    • Amicably resolved $25 million burn claim through negotiated settlement in multiple defendant litigation wherein we represented design professional who contributed to the design of a hydrogen furnace which exploded. Obtained settlement through small contribution by establishing limited liability for proximate cause of the accident.
    • Obtained summary judgment for a developer and general contractor in a construction defect case. The plaintiff, a homeowners association, sued multiple parties seeking $2.5 million in damages related to water infiltration due to the allegedly negligent installation of roofing, exterior cladding, windows, doors, railings and decks. We also represented several previous developer/association board members who were sued individually. Prior to filing suit, the plaintiff filed a claim with the state of New Jersey under the Home Owners Warranty program.
    • Obtained a defense verdict on behalf of a defendant engineering firm in a two week jury trial alleging negligence in the design of a subsurface disposal field.
    • Obtained dismissal of a negligent design claim against a design professional, after a three day Evidentiary Hearing (Lopez hearing) to establish the accrual date for the applicable Statute of Limitations. 

News

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Firm Highlights

Result

Summary Judgment Secured, Preserving $750,000 in Coverage for Insured in Major Trucking Liability Dispute

Ray Freudiger and Michael A. Roberts (both of Cincinnati) successfully obtained summary judgment on behalf of their client in a coverage dispute arising from a May 19, 2022, motor vehicle accident. A permissive driver operated a box truck for an interstate trucking company and caused severe injuries to two tort victims. Prior to the accident, the insured had procured a commercial auto policy for the trucking company with stated limits of $1,000,000. Following the accident, the insurer initiated a declaratory judgment action asserting that only reduced bodily injury limits of $25,000/$50,000 applied and later counterclaimed, alleging it would not have insured the driver had he been properly submitted for approval under the policy. After extensive discovery, briefing, and oral argument, the court rejected the insurer’s attempt to shift responsibility for the $750,000 in coverage it was legally required to provide for permissive drivers under Ohio law, granting summary judgment in favor of the insured and preserving $750,000 in liability exposure.

Portrait of Carolyn Schweizer, with text below: Philadelphia Office Managing Attorney

News

Marshall Dennehey Names Carolyn Schweizer New Philadelphia Office Managing Attorney

Thought Leadership

A Unified, Single Claim for Damages Requires Apportionment in a Joint Proposal: What the Decision in 'Trace Elements' Means for Property Insurance Claims

Kimberly and Seth, shareholders in the Insurance Services Practice in our Fort Lauderdale office, break down the Florida Supreme Court's decision in 'Trace Elements v. MacKensen' and what it means for property insurance claims in the state. Read the article here.

Marshall Dennehey Announces 2026 Ohio Super Lawyers and Rising Stars

News

Marshall Dennehey Announces 2026 Ohio Super Lawyers and Rising Stars

Thought Leadership

Appellate Division Affirms Dismissal of Legal Malpractice Counterclaim Against Martin Law Firm

In Martin v. Loury, 2026 N.J. Super. Unpub. LEXIS 1617 (App. Div. July 15, 2026), Martin Law Firm represented Kirk Loury in an employment matter Mr. Loury filed against his former employer, Concord Equity Group Advisors LLC (“Concord”). The allegations included, among other things, that Loury was not fairly compensated for his employment with Concord. After a bench trial finding in Loury’s favor, the Appellate Division remanded this matter in February 2016 for a second trial. During the second trial, Concord CEO, Lee Argush, testified to lower compensation estimate than first trial. On remand, the second trial judge awarded Mr. Loury the same damages as the first judge, finding Mr. Argush not credible. After the findings during the second trial, Martin Law Firm filed an action against Mr. Loury to recover legal fees and costs of representing Mr. Loury in a second bench trial and Mr. Loury filed a counterclaim against Martin Law Firm for legal malpractice, alleging he should have received an even higher award in the second bench trial. In this allegation, Mr. Loury, through his expert, claimed that Martin Law Firm should have recalled Mr. Loury to the stand to rebut Mr. Argush’s testimony to allege an alternative theory of damages. Mr. Loury’s expert admitted that the second judge already rejected Mr. Argush's theory and accepted Loury's damages theory. The trial court barred Mr. Loury’s expert and dismissed Loury's counterclaim with prejudice before convening the collection trial, and the jury ruled in Martin Law Firm’s favor. Mr. Loury appealed the trial court's pretrial rulings barring his liability expert from testifying in support of his legal malpractice counterclaim, denying his motion for summary judgment on that counterclaim, and denying his motion to amend his counterclaim by adding attorney Joseph A. Martin as a codefendant. In affirming the trial court’s decision, the Appellate Division held that the trial court properly excluded Loury’s expert testimony in the counterclaim against Martin Law Firm because the expert could not explain how calling Loury as a rebuttal witness would have increased damages when the second judge already rejected Mr. Argush's testimony and accepted Loury's damages theory, making the expert’s causation opinion speculative. The Appellate Division also held that the trial court properly denied Mr. Loury's summary judgment motion on his malpractice counterclaim because reasonable minds could differ on whether Mr. Martin's alleged failures would have changed the second judge's damages award, given the judge already found Mr. Argush not credible, creating genuine factual disputes precluding summary judgment. Also, the Appellate Division held that the trial court properly denied Loury's May 2023 motion to add Joseph Martin individually because the statute of limitations expired in February 2022, six years after the 2016 appellate remand when Mr. Loury incurred new legal costs, and relation back did not apply because Mr. Loury knew Mr. Martin's identity throughout and strategically chose to sue only Martin Law Firm in his 2019 counterclaim.

Jason Banonis Holds PDI Attorney of the Year Award with the PDI President

News

Jason Banonis Named Attorney of the Year by the Pennsylvania Defense Institute

Event

Pennsylvania Appellate Update 2025-2026

On August 21, 2026, Casey will serve as a panelist for the live webcast program, “Pennsylvania Appellate Update 2025-2026” presented by the Appellate Advocacy Committee of the Pennsylvania Bar Association and Pennsylvania Bar Institute. The program is divided into three parts—Criminal, Civil, and Administrative. Casey will serve as a panelist for the Civil portion, along with Christina McKinley of Blank Rome, Ben Baer of Injury Law Partners, John Masslon of Keller Postman, Jonathan Bruno of Bruno Litigation LLC, and moderator, Ezza Ahmed of Buchanan Ingersoll.  Registration and more information: https://www.pbi.org/product/pennsylvania-appellate-update-2025-2026/

Thought Leadership

Fla. Workers' Comp Physician Dispensing Ruling Could Produce New Legislative Fight

In a significant decision issued on February 25, 2026, the First District Court of Appeal (DCA) ruled in Publix Super Markets, Inc., et al. v. Department of Financial Services, et al., 430 So. 3d 252 (Fla. 1st DCA 2026), that while injured workers have an absolute right to choose their own pharmacy or pharmacist, that right does not extend to physicians who dispense medications directly to their patients.  Read Blake's article in Insurance Journal: https://www.insurancejournal.com/news/southeast/2026/08/05/880229.htm. 

blue facade of a hospital sign against blue sky

Result

Defense Verdict in Complex Medical Malpractice Trial

empty courtroom photo

Result

Summary Judgment Secured for Life Insurance Agent