Janis M. Berry received her B.A. from Boston University, magna cum laude (as a Phi Beta Kappa), and graduated from Boston University School of Law, cum laude. Justice Berry began her legal career serving as law clerk to Supreme Judicial Court Chief Justice Edward F. Hennessey. She worked in private practice for almost twenty years as a trial lawyer, including as a partner at the Boston law firms Ropes & Gray and Rubin and Rudman LLC, where she handled a wide variety of complex litigation matters. She served for six years as a federal prosecutor and was chief of the United States Justice Department's New England Organized Crime Drug Enforcement Task Force. Justice Berry also served on the Board of Bar Overseers and the Committee for Public Counsel Services. She was appointed chairperson of a United States Magistrate Selection Panel, was counselor to the Frank J. Murray Federal Inn of Court, and served as a member of the Governor's Judicial Nominating Council.
Justice Berry was appointed to the Appeals Court by Governor Paul Cellucci in 2001. As an adjunct professor, Justice Berry has taught advocacy courses at Boston University School of Law, Northeastern University School of Law, and Suffolk University Law School. She also has been an instructor at Harvard Law School and the United States Department of Justice Advocacy Institute and was on the board of advisors for the National Trial Competition. Justice Berry has published several articles, co-authored a treatise on criminal law, and served on the editorial board of the Massachusetts Law Review.