Karen Piso Nadeau is co-founding partner at Nadeau Harkavy LLC and devotes her practice to exclusively representing those injured in accidents. Karen is recognized as a distinguished personal injury lawyer concentrating her entire practice on representing victims and their families injured in accidents in Massachusetts.

She has more than 30 years of experience handling personal injury cases. In 1990, Karen joined a large prestigious firm in Cambridge as a summer associate while in law school, and her passion for representing those seriously injured in accidents due to the wrongdoing of others began and continues to this day. She spent her first 25 years of practice as an associate and trial attorney in law firms in Boston and Cambridge representing those seriously injured in accidents.

Karen has over 30 years of impressive settlements and verdicts and has built a reputation as an unrelenting champion for the rights of injured people across Massachusetts. She concentrates her practice in the areas of serious personal injury and wrongful death. Karen’s reputation of an unsurpassed work ethic and exceptional results negotiating, mediating, arbitrating, and going to trial make her stand out in the personal injury arena as recognized by those clients that have her advocating on their behalf and speak so highly of their experiences with her.

Karen successfully represents clients in a broad range of personal injury matters including wrongful death, motor vehicle accidents, pedestrian accidents, bicycle accidents, scooter accidents, truck accidents, unsafe premises and premise liability, trip and fall, dog bite, construction site accidents, motorcycle accidents, slip and falls, and liquor liability against individuals and businesses. She represents clients with brain injuries and catastrophic injuries that are life altering.

Knowledge & Experience

Karen has direct and close client communication building trust and relationships with her clients to address clients’ needs and concerns with a primary goal of placing her clients at ease and keeping them well informed about their case. Every interaction is seen as a building block to obtain the best possible outcome for her clients. She skillfully approaches every client and case with a desire and passion to get the best possible resolution for her clients and their families that have suffered a loss at the hands of someone else’s negligence.

Karen is highly skilled in negotiations with insurers, corporations, medical providers, lien holders and other attorneys. She uses her many years of experience and knowledge in the insurance industry to advocate for her clients injured in accidents, having represented insurance companies and defendants in numerous cases through settlement as well as trial. She uses her many years of experience and her drive for nothing short of excellence to obtain the best resolution through settlement negotiations or meticulous preparation and execution of litigation. She has developed an exceptional ability to evaluate the strengths and weaknesses for both sides of the case to make the best decisions for her clients in obtaining the most successful outcome.

Karen has personally litigated and negotiated many multi-million dollar cases over the past 30 years for her clients who have suffered injuries due to the negligence and wrongdoing of both individuals and companies. These cases include:

  • Representing a mother and her two children who were coming home from a vacation when a reckless driver crossed the double yellow line into their lane causing a horrific collision with their vehicle.
  • Karen also represented a pedestrian who was struck by a vehicle and suffered permanent deformity to her leg and foot.
  • She represented a father who was paralyzed as the result of a negligent driver who crashed into his vehicle.
  • She represented a family in a wrongful death case where their grandmother riding as a passenger was killed in a horrific car accident.
  • She also successfully negotiated a multi-million dollar case arising from a trip and fall on a business property resulting in catastrophic injuries.
  • She litigated, mediated, and successfully resolved a brain injury case arising from drunk driving and bars overserving a customer.
  • Karen represented a pedestrian run over by a construction vehicle on a property under construction causing numerous broken bones, inpatient hospitalization, rehab and lost wages.

These are just some of the many cases Karen has devoted her time and passion for her clients who placed their trust in her.  She is known to get to the bottom of what really happened -even when faced with evidence that disappears when a business owner tried to escape responsibility for example.

She will not rest until she knows she has done everything she can for her clients. She gives her full time and attention to each client and case using her many valuable contacts including experts and resources she has amassed over the past 30 years in the personal injury field in Massachusetts. She is not afraid to go toe to toe with those individuals or companies who have cause harmed to her clients. Her enthusiasm, work ethic and passion for victims who have been harmed is infectious, and she serves as a role model and mentor for younger lawyers taking the time to train and mentor them.

Before establishing her own law firm, Karen spent the last decade of her career in a law firm as senior associate where she developed and managed the personal injury department turning it into one of her greatest accomplishments. During this time, she had a caseload where she represented an insurance company and their insureds who caused the accidents and obtained inside knowledge and experience about how the other side of the case works. Having defended those negligent drivers and business owners against the victims that were harmed, gives her an edge in the personal injury field in Massahcusetts. Karen also handled serious injury and wrongful death cases where she shined not only as a top notch well respected personal injury lawyer representing those harmed, but also as human being who is a wife and mother, who was also there for her clients and their families in a time of need, making them feel heard and at ease knowing they had her in their corner. Karen also managed other attorneys, law clerks, paralegals, secretaries, and receptionists for more than a decade during her career. Her main focus was to make every employee, no matter what position they were in, to be the best they could be. She implemented and developed many systems and guidelines to make the personal injury department that she managed run as smoothly as possible with a standard of nothing less than excellence. No one could come close to Karen’s drive, standard of excellence, never giving up, and work ethic that she attributes to her father who she watched since a young child own and manage his own successful business here in Boston, Massachusetts with no college degree and nothing more than a high school diploma and passion and grit to succeed.

Karen established her own firm with her law partner Leslie Harkavy in 2019 with a focus on providing superb legal services in a boutique setting where she and her partner Leslie could focus on providing individual attention to clients, close communication with clients, and a commitment to the relentless pursuit of justice and top-quality representation to those injured and in need of compassion and support during one of the most difficult times in their lives. Having worked together for two decades as a team, Karen and Leslie have a track record of excellent results and satisfied clients, many who have become friends and refer other friends and family members to them for representation. They also are grateful for the referrals of accident cases by fellow attorneys who know them and trust that they will do everything they can to get their clients what they deserve.

Family & Community

Karen is a lifelong resident of Massachusetts. She grew up in Medford and Stoneham and has strong ties to friends, family, and community in the area. Karen is a happily married mother of a son and daughter. She is aware of the concerns every parent has when their children leave their sight. From daycare years to being away at college, she represents children and their families in tragic accident cases. Families often feel helpless, and worry takes over their lives that have been turned upside down. Karen is driven to comfort families and remove the stress with the claims and legal process so that they can concentrate on the well-being of their family. She finds representing children, from infants to college students, particularly rewarding and handles these cases with not just the aggressive tenacity of a veteran personal injury attorney but also with the sensitivity required to work with clients to ensure the best outcome during a time of immense grief and sadness. Karen is personally and professionally committed to holding individuals and companies accountable for their wrongdoing.

Karen graduated cum laude from Boston College and cum laude from Suffolk University Law School. She lives with her family and mini golden doodle in the Boston area. She enjoys devoting her time to charity and volunteer work focusing on children with disabilities and families in need. Karen is passionate about supporting women both professionally and personally. She recalls the days in her early career when she was the only female attorney in the court room or in a litigation meeting or deposition taking testimony. In furthering her cause for women in the law, Karen is cochair with her law partner, Leslie, of the solo and small firm committee of the Women’s Bar Association (WBA). Supporting women, career and personal development, education, mentoring, and networking are at the heart of this WBA committee where women can build friendships and professional relationships in an inviting atmosphere.

After spending her free time for many years in hockey rinks and dance studios where her son and daughter pursued their passions, she now enjoys watching her son’s journey with his first job out of college and her daughter’s college experience, both her children locally here in Boston where Karen has her roots both personally and professionally. Karen loves to run the Wakefield Lake with her husband and also enjoys Zumba with her fitness friends in her free time. Her local ties are an asset when representing those injured in accidents in Massachusetts.

Bar Admissions

  • Commonwealth of MA, 1992

  • US District Court, District of Massachusetts


  • Suffolk University Law School – J.D., Cum Laude 1992

  • Boston College – B.A., Cum Laude 1989

  • Nazareth Academy, Wakefield, MA 1985

Practice Areas

  • Personal Injury
  • Wrongful Death
  • Dog Bites
  • Automobile Accidents
  • Motorcycle Accidents
  • Trucking Collisions
  • Pedestrian and Bicycle Collisions
  • Premises Liability
  • Slip and Fall
  • Liquor Liability
  • Catastrophic Injury

  • Traumatic Brain Injury

  • Construction Site Accident

  • Alcohol Server and Social Host Liability

  • Child Injury

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Massachusetts Personal Injury Lawyers

Massachusetts Personal Injury Lawyers with over 60 Years Combined Experience Representing Those Injured in Accidents.