John A. Kiernan





40 Court St.

Boston, MA 02108

Practice Areas

Alternative Dispute Resolution

Class Actions, Collective Actions, and Mass Torts

Construction & Construction Defects


Entertainment, Sports & Recreation


Food & Beverage Liability



Premises Liability

Product Liability

Professional Liability




John is a founding partner based in the firm’s Boston office.  He has been trying cases for the past 40 years and currently concentrates in the areas of product and general liability claims, construction defect claims, professional liability claims - including physicians, architects, engineers, accountants and attorneys - and employment discrimination claims.  He also has tried, arbitrated and mediated significant commercial disputes arising from the sale or dissolution of partnerships, corporations and limited liability companies. He has tried more than 190 jury trials to verdict, including trials as long as three months.  

John also advises Fortune 500 corporations that are confronted with allegations of waste of assets, procurement fraud, loss of inventory and theft of proprietary information.  He has successfully managed special audit investigations that have resulted in the recovery of substantial monies lost to fraud, the removal of irresponsible management personnel and the criminal prosecution of wrongdoers identified by the investigation. These investigations have been conducted in a manner designed to identify and remove the perpetrators of fraud and corporate waste, to ensure compliance with appropriate standards of business ethics and to protect against potential retaliatory litigation.

John began his career as a prosecutor, serving for 14 years in the Office of the District Attorney for Suffolk County (Boston).  During his tenure as a prosecutor, he served as the Senior Trial Counsel for the Major Violators Division and served for eight years as the Chief of the Homicide Division.  Following his move to the civil practice of law, he was retained to represent the Governor of the Commonwealth, as well as the Massachusetts Attorney General and the Secretary of Public Safety.  

John also served on the faculty of the National College of District Attorneys from 1982 until 1987.  He has been an adjunct Professor of Law at the New England School of Law, since 1987, concentrating in criminal procedure courses.  Additionally, he has served as an arbitrator for the resolution of cases pending in the courts of the Commonwealth.  John’s civic and professional activities also buttress his trial practice.  His work in environmental litigation has been enhanced by his role as a Conservation Commissioner for the Town of Milton, since 1993, where he currently serves as the Commission Chairman.

Court Admissions

  • Massachusetts 
  • U.S. District Court for the District of Massachusetts
  • U.S. Court of Appeals for the First Circuit

Notable Matters

  • He has argued before both state and federal courts in 54 appeals, including a recent matter before the Third Circuit, involving a significant issue of federal preemption, arising from the FDA’s regulatory powers.  
  • He has successfully presented matters of first impression before the Massachusetts Supreme Judicial Court, including matters of constitutional importance involving religious freedom, the division of power among the several branches of government and the principle of one person/one vote.

Publications & Presentations

John has presented seminars to numerous professional associations, including the Defense Research Institute, the Boston Bar Association, the Massachusetts Academy of Trial Attorneys, the National District Attorneys Association, the American Prosecutors’ Research Institute, the American Society of Industrial Security, the National Association of Medical Examiners and the Institute of Internal Auditors.


  • Harvard University, B.A. cum laude, 1970 
  • Boston University, J.D., 1974

Professional & Community Affiliations

  • Member, Massachusetts Bar Association
  • Member, Federal Bar Association
  • Member, National Association of Railroad Trial Counsel
  • Member, Defense Research Institute
  • Massachusetts Juvenile Advisory Committee
  • The Massachusetts District Attorneys Association 
  • Legislative Committee (Chairman), and the Massachusetts Medical Legal Commission

Previously served on the Superior Court Study Commission Rules Committee to revise the Criminal Rules of procedure.  He also served on the Massachusetts Judicial Nominating Council (“JNC”) from 1996 until 2003, including holding the position of chairman of the Eastern Region of the JNC and as a member of the Executive Committee for the statewide Council.