Karen F. Green


Green, Karen F.

Karen Green's practice concentrates on complex business litigation, including the defense of white-collar criminal and False Claims Act litigation. She has extensive experience representing companies in high-stakes government investigations and litigation of alleged fraud, bribery, conspiracy and violations of federal statutes, including the Anti-kickback Statute, the Food Drug and Cosmetic Act, the Foreign Corrupt Practices Act, the Export Control Act and securities laws. At the request of corporate clients, she also has conducted numerous internal investigations of alleged wrongdoing and has advised their boards on compliance issues. Ms. Green has been selected as among the top investigations lawyers in the world, and has been consistently recognized by legal publications as a leader in litigation, including the defense of government and white collar criminal investigations and litigation.

From 1993 to 1996, Ms. Green was the Deputy US Attorney for the federal District of Massachusetts. She supervised the investigation and prosecution of criminal cases and the litigation of civil cases on behalf of the United States. She also led the office's civil and criminal healthcare fraud enforcement program and served on the Department of Justice's National Health Care Fraud Working Group.

Ms. Green first joined legacy Hale and Dorr as a litigation associate in 1982. From 1984 through 1986, she served as an assistant US attorney in the Civil Division of the US Attorney's Office in Boston. She was appointed deputy chief of the Civil Division in June of 1986, and successfully obtained summary judgment on behalf of the EPA in a lawsuit compelling the cleanup of Boston Harbor. In January of 1987, Ms. Green returned to Hale and Dorr. She was elected to junior partnership in 1988, and to senior partnership in 1990. During the period from 2000 to 2007, Ms. Green served as vice chair and chair of Hale and Dorr’s Litigation Department and as co-chair of WilmerHale’s Litigation/Controversy Department. She also served as a member of the firm’s Executive Committee.

In 1993, Massachusetts Governor William F. Weld appointed Ms. Green his chief of staff. She co-chaired governor-elect Weld's transition team for the Executive Office of Health and Human Services in late 1990 and early 1991.

Ms. Green is admitted to practice in the Commonwealth of Massachusetts, the US District Court for the District of Massachusetts, the US Court of Appeals for the First Circuit, the US Court of Appeals for the Federal Circuit and the US Supreme Court.

Ms. Green received her JD, cum laude, from Harvard Law School, and is a magna cum laude graduate of Harvard and Radcliffe Colleges, where she was elected to Phi Beta Kappa. She served as a law clerk to US District Court Judge W. Arthur Garrity, Jr.

Honors & Awards

  • Selected by peers for inclusion in the 2008-2015 editions of the Best Lawyers in America in the area of white-collar criminal defense
  • Selected by clients and peers as being among the world's leading investigations lawyers in the 2015 edition of Who's Who Legal: Investigations and Who's Who Legal: Business Crime Defence
  • In the 2011–2012 Best Law Firm rankings by U.S. News – Best Lawyers, a client described Ms. Green as "very bright, knowledgeable, and direct."
  • Recognized as one of Massachusetts’ leading lawyers in the field of healthcare law in the 2014 edition of Chambers USA: America's Leading Lawyers for Business, and praised by clients as “extremely detail-oriented, very strategic and always thinking about the best interests of her clients.” Ms. Green was also recognized in Chambers USA for her work in litigation, specifically in white-collar crime and government investigations, from 2005-2013.
  • Named a "Life Sciences Star" in the 2012, 2013 and 2014 editions of LMG Life Sciences
  • Selected in 2011 as one of "Top Women of Law” by Massachusetts Lawyers Weekly
  • Listed as a "leading lawyer" in the field of government enforcement & investigations law by the PLC Cross-border Life Sciences Handbook, 2009/2010
  • Recognized in The International Who's Who of Investigations Lawyers 2014, listing the most highly-regarded investigations lawyers in the world. Also selected for inclusion in The International Who's Who of Business Crime Lawyers in 2008-2010 and 2011-2014, with sources recently saying she's a "first-class litigator." 
  • Named to Lawdragon magazine's "500 Leading Lawyers in America" list in 2015. Also listed in the 2006 and 2013 editions of Lawdragon for her work on behalf of pharmaceutical, medical device and other healthcare companies.
  • Named a "New England Super Lawyer" (formerly "Massachusetts Super Lawyer") in white-collar criminal defense in the 2005-2014 issues of Boston Magazine. Ranked among the "Top 50 Women Massachusetts Super Lawyers" in 2004, 2006, 2012, 2013 and 2014 and as one of the "Top 100 Massachusetts Super Lawyers" in 2004 and 2005.
  • Recognized in Lawyer Monthly magazine's Women in Law Awards in 2014, an annual list highlighting the achievements of women in the legal professional across the globe.
  • Fellow, Litigation Counsel of America (Member, Thomas A. Mesereau Cup Selection Committee)
  • Honoree, Granada House Annual Dinner, 2002, for pro bono legal work on behalf of group home for disabled persons
  • Recipient of the 2001 Women's Business Hall of Fame Award in the professional category
  • Recipient of the Patriots' Trail Girl Scout Council, Inc.'s Leading Women 2000 Award
  • Recipient of the Park Street Forum's Award for Outstanding Service to the City of Boston in 1997
  • Profiled as one of Boston's Top Women Lawyers, The Boston Globe, 1996

Publications & News


January 29, 2015

False Claims Act: 2014 Year-in-Review

The federal government collected a record-breaking $5.7 billion in False Claims Act (FCA) recoveries in fiscal year (FY) 2014, up from $3.8 billion in FY 2013.

October 21, 2014

Karen Green Featured in Cover Story of New England Super Lawyers

Partner Karen Green is featured on the cover of the 2014 New England Super Lawyers Magazine and is the subject of its story, "The Details and the Big Picture."

August 28, 2014

LMG Life Sciences Honors Firm, Attorneys with Top Rankings for Third Consecutive Year

The 2014 edition of LMG Life Sciences has been released, and it includes the recognition of nine WilmerHale practice areas and 17 attorneys.

May 23, 2014

Chambers USA Ranks Top WilmerHale Lawyers and Practices in 2014 Edition

We are pleased to announce the names of the individuals and practice areas that are ranked in the 2014 edition of Chambers USA: America's Leading Lawyers for Business.

April 9, 2014

Testify First, Know Why Later: Responding to Civil Investigative Demands for Testimony in False Claims Act Cases

An article by Karen Green and James Fauci, published in the April 2014 edition of Financial Fraud Law Report.

March 25, 2014

Minding the Monitor: Disclosure of Corporate Monitor Reports to Third Parties

An article by Karen Green and Timothy Saunders, published in the March 25, 2014 edition of Bloomberg BNA's The United States Law Week.

February 24, 2014

Fourth Circuit Holds cGMP Violations Do Not Create False Claims Under Medicare and Medicaid

In the first appellate decision of its kind, the U.S. Court of Appeals for the Fourth Circuit held on February 21, that because compliance with the Food and Drug Administration’s Current Good Manufacturing Practices (cGMP)  regulations is not a precondition for reimbursement under Medicare and Medicaid, violations of the cGMP regulations by themselves cannot form the basis for False Claims Act claims under those programs.

January 7, 2014

False Claims Act: 2013 Year-in-Review

The False Claims Act (FCA) saw another year of increased activity in 2013, with new qui tam suits hitting an all-time high of 753, a rise of more than 100 over 2012. In fiscal year 2013, the federal government brought in $3.8 billion—the fourth year in a row of more than $3 billion in recoveries. As in the past, the healthcare and pharmaceuticals sector accounted for the biggest share, with $2.6 billion recovered. Procurement saw a jump, more than doubling to $890 million. Financial institutions remained a substantial target, and both the government and private plaintiffs were increasingly bringing claims against recipients of grant and loan funds as well as contractors. Activity at the state level increased as well, with many states expanding the reach of their own false claims statutes, and both state attorneys general and private plaintiffs making aggressive use of new theories of liability.

August 15, 2013

Best Lawyers in America® 2014 Recognizes Nearly 100 WilmerHale Partners, Naming Eight “Lawyer of the Year”

Nearly 100 WilmerHale lawyers have been selected for inclusion in the 20th edition of The Best Lawyers in America®—a respected peer-review publication in the legal industry.

June 20, 2013

FDA Issues Draft Guidance on Cybersecurity Considerations in Premarket Submissions for Medical Devices

On June 14, the Food and Drug Administration (“FDA”) issued draft guidance on the content of premarket submissions for management of cybersecurity in medical devices.

Recent Highlights

As select examples, Ms. Green has represented:

  • an Internet search and technology company in a grand jury investigation of alleged aiding and abetting of unlawful conduct by Canadian online pharmacies;
  • a device manufacturer in connection with the resolution of claims that it had breached a deferred prosecution agreement;
  • an international development organization in an internal investigation into the conduct of one of its senior officers;
  • a public company in a grand jury investigation of alleged government program fraud;
  • a former officer of a major public company in an FCPA investigation;
  • a major pharmaceutical company in parallel criminal and civil investigations of alleged off-label promotion and improper payments in connection with the marketing of six drugs, and assisted it in globally resolving those investigations, four related qui tam actions, and related administrative claims;
  • a medical device manufacturer in a grand jury investigation by the US Attorney for the District of New Jersey and assisted it in globally resolving the government’s criminal, civil and administrative claims;
  • a major medical device manufacturer in a six-year, grand jury investigation by the United States Attorney's Office in Boston into the distribution of an allegedly adulterated and misbranded stent delivery system; the matter was resolved on a civil basis and neither the company nor two officers, who had been designated as targets, were indicted;
  • a defense contractor in a qui tam action, which was dismissed with prejudice, under the False Claims Act;
  • a third party billing company in parallel civil and criminal investigations by the US Attorney for the Southern District of New York of alleged Medicare and Medicaid fraud;
  • a supplier of durable medical equipment in a grand jury investigation by the US Attorney for the Southern District of Florida of alleged Medicare fraud;
  • multiple former employees in civil and criminal investigations by the US Attorney for the District of Massachusetts of alleged off-label marketing of a drug;
  • an office products supplier in a qui tam False Claims Act suit filed in the District of Columbia allegedly arising from the sale of office supplies to the US government that originated from impermissible countries under the Buy American Act;
  • a medical device manufacturer in an investigation by the US Attorney for the District of Massachusetts arising from the sale of allegedly defective blood analyzers to the US Army;
  • a medical device manufacturer in an investigation by the US Attorney for the District of Columbia of alleged violations of the Export Control Act;
  • a printed circuit board manufacturer in a criminal case charging violations of the federal Clean Water Act;
  • the former President and CEO of a health insurer in a federal grand jury investigation;
  • a company's former CEO and director in parallel civil, criminal and Congressional investigations of alleged improprieties in government contracting;
  • a national retailer in parallel civil and criminal proceedings alleging bankruptcy and mail fraud; and
  • various companies in corporate internal investigations.

Professional Activities

Ms. Green is a director, chair of the Finance committee, and member of the Executive and Audit committees of CareGroup, Inc., an organization of teaching and community hospitals, physician groups and other caregivers. She also is a trustee of Massachusetts Eye and Ear, a director of the Harvard Club of Boston, a fellow and state delegate co-chair of Litigation Counsel of America and a member of the Trial Law Institute and the Diversity Law Institute. She is also a trustee and executive committee member of the Massachusetts Taxpayers Foundation, as well the chair of its seven-member Search Committee tasked with selecting the Foundation's new president. Ms. Green also formerly served as a director of Fiduciary Trust Company and as a trustee of The Fenn School.

Ms. Green was appointed to a special commission charged with investigating allegations of inmate abuse and financial mismanagement at the Suffolk County Sheriff's Department. She also formerly served as: vice chair of the Massachusetts Supreme Judicial Court's Committee on Pro Bono Legal Services; a member of the First Circuit Court of Appeals’ Advisory Committee on the rules of practice and internal operating procedures, the First Circuit Court of Appeals' Gender Bias Committee, the US District Court's Committee to Revise the Local Criminal Rules, the US District Court's Committee on Alternative Dispute Resolution, the Boston Bar Association Council, and the Executive Committee of the Massachusetts Judicial Nominating Council; a director of the Harvard Alumni Association, the Boston Club, and the Children's Trust Fund; an instructor in Harvard Law School's Trial Advocacy Workshop and the United States Attorney General's Advocacy Institute; a trustee of the Boston Bar Foundation; and chair of the Boston Bar Association's Federal Practice and Procedure Committee.


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JD, cum laude, Harvard Law School, 1981

AB, magna cum laude, Harvard University, 1978, Phi Beta Kappa

Bar Admissions


New York

United States Supreme Court


The Hon. W. Arthur Garrity Jr., US District Court for the District of Massachusetts, 1981 - 1982