Siobhan M. Sweeney defends businesses in employment and labor litigation, conducts sensitive investigations, and provides legal counsel and advice on all aspects of the employment relationship. 

Siobhan’s litigation practice includes first and second chair trial experience, defense of employers in state and federal courts, agencies and arbitral forums throughout the Northeast and Midwest regions including the Equal Employment Opportunity Commission (EEOC), the Department of Labor (DOL), Occupational Safety and Health Administration (OSHA) and Financial Industry Regulatory Authority (FINRA). Her experience includes defense of claims for violation of laws related to:

  • Discrimination (race, gender, religion, national origin, age, disability, gender identity, e.g. sexual orientation)
  • Whistleblower and retaliation
  • Contract and quasi-contract
  • Leaves and accommodations
  • Defamation
  • Employment torts

Siobhan provides practical and business-focused advice to employers on a wide variety of workplace issues, including leaves of absence, accommodations, employee discipline and discharge, employment and separation agreements, hiring, employment policies and handbooks, internal investigations and compliance.  

Professional & Community Affiliations


American Bar Association


Boston Bar Association


appointed since 2010

Massachusetts State Advisory Committee to the U.S. Civil Rights Commission


Named, The Best Lawyers in America®


Named, Super Lawyer

New England

Super Lawyers

2009-2012, 2014-2016

Named, Rising Star

New England

Super Lawyers


Speaking Engagements

Accommodating Mental Health Issues in the Workplace

2019 New England Employer Conference, Newton, MA

September 27, 2019

#NotYouToo: How to Conduct Legal Investigations in the Aftermath of #MeToo

Boston, MA

June 11, 2019

Paid Family and Medical Leave, Marijuana, and Other Hot Topics For Massachusetts Employers

Boston, MA

April 11, 2019

2018 Employment Law Update

Boston, MA

June 8, 2018

Emerging Pay Equity Laws - How to Advise Your C-Suite and Safeguard Your Company

March 15, 2017

Investigations: The Corner Stone of Effective EEO Policies and Codes of Conduct

2016 New England Employer Conference, Burlington, MA

October 13, 2016


  • J.D., Boston University School of Law, 1992
  • B.A., University of Virginia, 1988

Bar Admission



  • U.S. Supreme Court
  • U.S. District Court, District of Massachusetts
  • U.S. Court of Appeals, 2nd Circuit