Mary Kate Mullen



Kate has over 25 years of litigation experience. Prior to joining Biedermann Hoenig Semprevivo, Kate was an Assistant District Attorney for eight years in Suffolk County, New York, and was in private practice where she concentrated on criminal defense and personal injury cases. 

Kate focuses her practice on defending companies and educational institutions in a wide range of litigation matters including product liability, premises liability, and a variety of claims concerning school setting and athletic event supervision. She has conducted trials, arbitrations, and mediations and has significant appellate experience.

In 2015 Kate was elected as a Councilwoman for the Town of Islip and serves as one of four council members on the Islip Town Board. Islip, with a population of over 335,000 people, is the third largest town in New York State, and is located on the south shore of Long Island. As councilwoman, Kate’s responsibilities include approval of budgets, enacting legislation, and regulating land use.


  • J.D., St. John’s University School of Law
  • B.A., English & Political Science, Fairfield University

Memberships and Affiliations

  • New York State Bar Association
  • Suffolk County Bar Association
  • Greater Long Island Road Runners Club
  • Islip Opioid Task Force

Bar Admissions

New York

Court Admissions

Eastern District of New York

Reported Cases

  • Calderone v. Molloy College, 177 A.D.3d 692 (2d Dept. 2019)
  • People v. Gregory Love, 282 A.D.2d 550 (2d Dept. 2001)
  • People v. David Casper, 287 A.D.2d 575 (2d Dept. 2001)
  • People v. Luis Fernandez, 291 AD2d 456 (2d Dept. 2002)