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Peter Lawrence MacIsaac

also known as Peter L. MacIsaac, Peter MacIsaac

About Me

Peter L. MacIsaac is a Certified Civil Trial attorney and is recognized as one of the most accomplished plaintiff's catastrophic injury and medical malpractice trial lawyers in the state of New Jersey. Peter represents clients in all types of personal injury matters including auto accidents, general negligence and dangerous premises liability.  The eldest son of a corporate lawyer and a licensed clinical social worker (LCSW), Peter decided at a young age that he wanted to be a trial lawyer.

Peter focuses his practice on representing patients and their families who have been harmed by preventable medical errors.  Peter has successfully procured compensation for patients and their families who were injured as a result of negligent medical care.  He has had primary responsibility for cases involving various fields of medicine including obstetrics; surgery; oncology; gastroenterology; cardiology; neurology; neurosurgery; emergency medicine; and infectious diseases, among others.  Many of these patients have needlessly suffered wrongful death or been unfairly deprived of the opportunity to treat or cure their terminal illness.  Several have ended up in a comatose like state or have been permanently inflicted with cerebral palsy or other forms of brain damage, as a result of medical error.

Peter has tried several important cases through to verdict including medical malpractice matters involving wrongful death, auto and premises liability, estate commercial/contractual (fraudulent transfer) and real estate matters.  He has also argued before the Appellate Division of the Superior Court of New Jersey; the Supreme Court of New Jersey; the United States District Court for the District of New Jersey; and the United States Court of Appeals for the Third Circuit. 

In 2010 and 2011, Peter was named a Rising Star® by New Jersey Super Lawyers® for his efforts representing victims of professional medical negligence.  He has also been appointed to the New Jersey State Bar Association’s Special Committee on Medical Malpractice.  In 2012 Peter was named one of the top 100 trial attorneys in the state of New Jersey by the National Trial Lawyers.

In addition to representing patients damaged by medical negligence, Peter also represents victims of general negligence, including those injured by driver error, as well as dangerous premises and products.  

Peter also represents parties in commercial and chancery matters.  In 2005, the United States Court of Appeals for the Third Circuit adopted Peter’s arguments for its precedent setting interpretation of the Computer Fraud and Abuse Act (“CFAA”).  See Party City v. Celebration, et al., 428 F. 3d 504, C.A.3 (N.J) (No. 04-4254).  Peter successfully defended an individual charged with computer hacking the business of a competitor to steal trade secrets.  He argued this case before the Federal District Court for the State of New Jersey and the United States Court of Appeals for the Third Circuit. The Precedential Opinion is available on-line at

Peter worked directly under one of Chasan Leyner & Lamparello's  founding members, Joel A. Leyner for several years after joining the firm and before assuming primary responsibility for the firm’s catastrophic injury and medical malpractice matters.  Prior to that time, Peter had worked as a transactional attorney in commercial real estate matters and had handled the defense of various personal injury matters for ShopRite and other defendants. During his time as an associate, Peter had primary responsibility for discovery in the firm’s medical malpractice cases and was instrumental in the successful resolution of many cases, resulting in a large amount of multi-million dollar verdicts and settlements.  



Languages Spoken: Spanish, English

Photos and Videos

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Practice Areas


  1. Medical Malpractice: 60%
    14 years
  2. Litigation: 40%
    14 years



Contingent (25-33%)

Payment Types:


Attorney Endorsements

4 total 

  • Joseph A Rutigliano

    I endorse this lawyer.


    Joseph Rutigliano Real Estate Attorney
    Relationship: Fellow lawyer in community

  • Glenn R Reiser

    Peter is a pleasure to work with. He is very conscientious, and is easy to communicate with - promptly returns phone calls and is very responsive to emails. He is also highly skilled in his profession, demonstrating excellent oral advocacy and an in-depth knowledge of the law. Peter is also associated with a law firm whose excellent reputation in the New Jersey legal community equally matches his. I highly recommend Peter.


    Glenn Reiser Litigation Attorney
    Relationship: Worked together on matter

Contact Info

Chasan Leyner & Lamparello

300 Harmon Meadow Boulevard
Secaucus, NJ, 07094-3642



Professional Misconduct

We have not found any instances of professional misconduct for this lawyer.
Avvo Contributions
Legal Answers
Award NameGrantorDate Granted
Certified Civil Trial AttorneyNJ Supreme Court2015
The Top 100 Trial Lawyers-New JerseyThe National Trial Lawyers2012
Rising Star -Plaintiff's Medical MalpracticeNJ Super Lawyers Magazine2011
Rising Star -Plaintiff's Medical MalpracticeNJ Super Lawyers Magazine2010
Work Experience
TitleCompany NameDuration
PartnerChasan Leyner & Lamparello, PC2014 - Present
AssociateChasan Leyner & Lamparello, PC2003 - 2014
Association NamePosition NameDuration
National Trial Lawyers AssociationTop 100 Trial Lawyers -New Jersey2012 - Present
New Jersey State Bar Association Special, Special Committee on Medical MalpracticeVice Chair2011 - Present
New Jersey Association for JusticeMember2010 - Present
New Jersey State Bar AssociationMemberN/A
Hudson County Bar AssociationMemberN/A
Hudson Inn of CourtMemberN/A
Legal Cases
Case NameOutcome
Party City v. Celebration, et al., 428 F. 3d 504, C.A.3 (N.J) (No. 04-4254).Dismissed
Alicia Warren as g/a/l of Jazmine Warren a Minor v. The East Orange Board of Education, ESX-L-2570-09Settled for $1,500,000
Estate of Kiomara Hernandez v. St. Joseph's Regional Medical Center; Edward Glavey, DO; Janet Arribas, DO, PAS-L-1685-09Settlement $1,100,000
See all Legal Cases 
School NameMajorDegreeGraduated
Seton Hall University School of LawLawJD - Juris Doctor2000
Seton Hall UniversityN/ABA - Bachelor of Arts1996