New York School of Law, J.D. (Recipient of Dean’s Scholarship)
Yale University Parkinson’s Disease Research
Laboratory – Medical Assistant and Research Assistant
University of San Diego, B.A., Cum Laude


New York

New Jersey


U.S. District Courts – Southern and Eastern Districts of New York

U.S. District Court for the District of New Jersey


NY State Medical Defense Bar Association

New York State Bar Association

New York County Lawyers’ Association

NY State Academy of Trial Lawyers

Defense Research Institute

Physicians Insurers Association of America

Professional Liability Defense Federation



  • Medical Malpractice

  • Dental Malpractice

  • Nursing

  • Chiropractic

  • Podiatric

  • Disciplinary Proceedings & Professional Licensing

  • Nursing Home and Long Term Care

  • Premises Liability

  • Products Liability Defense

  • General Liability

  • Municipal Liability

  • Business & Contract Law for Healthcare Professions

  • Appellate Practice




William is a founding Partner who represents healthcare providers in virtually all medical specialty fields. He is a former Assistant Corporation Counsel to the City of New York – Medical Malpractice Division, and prior to forming Spiegel Leffler PLLC, he spent 10 years as founding Partner and Trial Counsel to a respected medical and dental malpractice defense firm in New York City.

Mr. Spiegel is a trial attorney with multiple verdicts in medical and dental malpractice actions, as well as general liability actions. He has obtained defendants’ verdicts in high-exposure trials in Bronx County, Kings County, Queens County, Richmond County and New York County. He also represents many physicians before the Office of Professional Medical Conduct and dentists before the Office of Professional Discipline.

William has further expertise in defending nurses, chiropractors, optometrists, psychiatrists, speech therapists, physical therapists, audiologists, massage therapists and medical clinics. He has also successfully argued several appeals before the First and Second Departments.


Mr. Spiegel regularly lectures to dental students at the Columbia University College of Dental Medicine and the New York University College of Dentistry.


  • Chosen by Super Lawyers Magazine as a New York “Super Lawyer” for 2013, 2014, 2015, 2016, 2017 and 2018. Super Lawyers is a rating service of outstanding lawyers from more than 70 practice areas who have attained a high degree of peer recognition and professional achievement. The selection process is multi-phased and includes independent research, peer nominations and peer evaluations. Only 5% of practicing attorneys in New York achieve this designation.

  • Selected by his peers as one of the top 100 medical malpractice defense lawyers in the New York City metro area in 2017.

  • Named in the top 1% of trial lawyers in the state of New York for 2012, based solely on actual trial results.

  • Recognized by Martindale-Hubbel with a rating of “AV Preeminent,” that organization’s highest peer review rating achievable, based on legal ability and ethical standards.