900 Elm Street
10th Floor
Manchester, NH 03101
Tel: 603 628 1490

Margaret "Peg" O'Brien

Director, Litigation Department

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Peg O’Brien assists employers with legal compliance and risk management in all phases of the employment relationship, as well as defense of employers in matters pending before government agencies and courts.  On a regular basis, Peg assists company executives, human resources professionals and supervisors with routine employment law concerns including:

  • Employee handbooks and related employee policies;
  • Hiring (offer letters and employment agreements);
  • Non-compete, Non-solicitation and Nondisclosure Agreements;
  • Independent Contractor Agreements;
  • Wage and hour compliance, including employee classifications such as exempt vs. nonexempt;
  • Guidance with employee leaves of absence;
  • Management of employee performance and expectation setting, including drafting performance improvement plans;
  • Disciplinary action including review and discussion of any litigation risks, and drafting documentation of warnings and termination letters;
  • Drafting severance agreements; and
  • Management of employee workplace complaints, including investigations and interpersonal conflict between employees.


Peg provides on-site and virtual training for employees and supervisors on harassment prevention, documentation and discipline best practices, and other employment law matters.

In addition, Peg conducts workplace investigations as an internal or outside independent investigator, and recently completed the Massachusetts Commission Against Discrimination’s Certified Course on Conducting Discrimination Complaint Investigations.  Peg frequently presents at seminars on employment law issues before human resources and trade groups.  She has practiced law for more than 25 years and has handled litigation in federal and state courts throughout New Hampshire.  She has extensive jury trial experience as well as extensive experience appearing before government agencies.  Prior to entering private practice, Peg began her legal career as an attorney with the New Hampshire Public Defender Program. 

Peg received her JD from The George Washington University Law School and her BA in Computer Science from Colgate University.


  • New Hampshire
  • Massachusetts



  • Granite YMCA, Chair (2010-present)
  • New Hampshire Public Defender Program, member (2014-present)
  • CASA of NH, member (1995-2000)
  • New Hampshire Bar Employment Law Section, Past Chair (2012-2014)
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Speaking Engagements

  • Vaccines in the Workplace (webinar, NH Motor Transport Association, 5/6/2021)

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Practice Areas

The strengths of our practice groups and the industries we serve make McLane Middleton one of the most diverse law firms in New England.


With a focus on our clients’ business, we continue to build our practice differently, harnessing the expertise and competitive nature of smart attorneys and professionals to work collaboratively and guide our clients through the complexities of law. 

Integrity and trust

At McLane Middleton we establish and maintain long-standing relationships with our clients to help us better achieve their unique goals over time. This approach to building trust requires that our esteemed lawyers and professionals use their broad, in-depth knowledge and work together with integrity to ascertain sound resolutions to legal matters for their clients.

Strength in numbers

McLane Middleton is made up of more than 105 attorneys who represent a broad range of clients throughout the region, delivering customized solutions. As a firm we are recognized as having the highest legal ability rating. The firm is rated Preeminent by Martindale Hubbell and is recognized as one of the nation's leading law firms in Chambers USA. Our attorneys are distinguished leaders in their respective practice areas.

Meet Our People

Commitment and collaboration

McLane Middleton's versatile group of attorneys and paralegals become trusted authorities on each case through collaboration. We work with our clients to learn their individual needs first and foremost and, together, we develop comprehensive solutions to their specific legal matters. This approach helps us exceed our clients' expectations efficiently and effectively, client by client, case by case.

Practice Areas

A history of excellence

McLane Middleton was established in 1919 in New Hampshire, and has five offices across two states. However, deep historical roots don't allow you to become innate. Our firm is organized, technological, and knowledgeable. Our history means we are recognized. But our reputation is built on the highest quality of service and experience in very specific areas of law.

The Firm

Intelligence paired with action

Our team continuously seeks opportunities to enhance their professional development and put key learnings to action. The pursuit of further insight guides us to volunteer service opportunities, speaking engagements, and teaching roles. Our lawyers are sought after thought leaders across their industries, and recipients of leadership awards throughout the region.