David is Preti Flaherty's Managing Partner. In that role, David oversees all aspects of the firm's operations and, along with the Management Committee and Chief Operating Officer, sets strategic goals and operational objectives for the firm. A nationally recognized environmental lawyer with a distinguished career at the U.S. Environmental Protection Agency (EPA) in Washington, D.C., David joined Preti Flaherty in 1991 and became chair of the firm's Environmental Practice Group in 1995.

He is an active participant in all aspects of the firm's environmental practice, including litigation, compliance counseling, liability allocations, environmental audits, defense of enforcement actions, project permitting, due diligence in business and lending transactions and environmental risk management.

David also has testified in U.S. District Court as an expert witness related to EPA policy and procedures and managed CERCLA liability allocation efforts at several significant Superfund sites.

EPA Experience
David represented the EPA at the negotiating table and participated at the highest levels of the agency's compliance and policy-making efforts. He now offers clients a unique, insider's view of Federal environmental law based on his extensive EPA experiences:

  • As Acting Associate Enforcement Counsel for Superfund and, prior to that, as Deputy Associate Enforcement Counsel for Hazardous Waste, David managed the nationwide implementation of the EPA's civil judicial enforcement programs under CERCLA and RCRA.
  • As Chair of the CERCLA Lender Liability Rule Task Force, David supervised the development of the agency's lender liability rule and the issuance of the agency's first prospective purchaser guidance, approving the initial brownfields-type settlements. Upon joining Preti Flaherty, David was instrumental in the passage of Maine legislation creating liability protections for lenders and establishing Maine's brownfield VRAP program.
  • As the EPA's lead headquarters attorney litigating the precedent-setting U.S. v. Conservation Chemical Superfund cleanup case, involving more than 200 defendants and third-party defendants, David pushed the case to a successful conclusion. The case was one of the first to be litigated under Superfund.
  • David's awards while at the EPA included the Department of Justice Commendation for Outstanding Service; the Assistant Administrator's Enforcement Award for Excellence; a Silver Medal; two Bronze Medals; and numerous Superior Performance and Outstanding Achievement Awards.

Prior to joining the EPA, David was a legal policy analyst for Booz-Allen and Hamilton, Inc., in Washington, D.C., where he helped develop policy on civil judicial and administrative enforcement for the EPA's hazardous waste programs. He also worked for Environmental Research and Technology in Washington as a legislative and policy analyst, focusing on legislative initiatives under the Clean Air Act and Clean Water Act.

Professional Activities

  • New England Interstate Water Pollution Control Commission
    • Commissioner, 2013-Present
  • Maine State Bar Association
    • Member, Environmental and Energy Law Section
  • American Bar Association
    • Member, Section of Environment, Energy, and Resources 
  • Cumberland County Bar Association

Honors & Recognition

  • Chambers USA, Band 1 Environment Lawyer, 2006-Present
  • Listed in Best Lawyers in America 2005-Present
    • 2020 Lawyer of the Year, Environmental Law
  • Martindale-Hubbell® AV Preeminent™ Peer Review Rating
  • Listed in New England Super Lawyers
  • Fellow – American College of Environmental Lawyers
  • Fellow – American Bar Foundation; Maine Bar Foundation

Civic and Charitable Activities

  • Maine Adaptive Sports and Recreation
    • President and Chair of Board, 2014-2016
    • General Counsel, 2018-Present
    • Executive Committee, 2005-2010, 2012-2014, 2016-2018
    • Vice President, 2005-2010, 2012-2014
    • Board Member, 1999-2018
    • Board Governance Committee, 2007-2018
    • Volunteer/Fundraiser, 1991-Present
  • Royal River Conservation Trust
  • Royal River Recreation Authority, Development Task Force
  • Volunteer Lawyers Project
  • Soccer Maine Licensed Soccer Coach
  • U.S. Youth Soccer Association Certified Referee
  • Leadership Maine, Mu Class, Maine Development Foundation
  • Maine State Chamber of Commerce, Environment and Energy Committee Member

Firm Highlights


Racial Justice Fund Seeks Applications for Second Round of Grants

The Maine Justice Foundation is pleased to announce the second round of grants from the Racial Justice Fund. The Foundation will accept applications for grants of up to $10,000 from June 1-15, 2022. The...


Maine Justice Foundation Awards Grants to Seven Maine Groups Working for Racial Justice and Equity

The Maine Justice Foundation has awarded grants from its Racial Justice Fund to seven Maine groups for 2022. The goal of the Fund is to support Black, Indigenous, and People of Color statewide to...


Sixteen Preti Flaherty Attorneys Selected as Chambers USA Leaders in Their Field

Sixteen Preti Flaherty attorneys and six practice groups have been selected for inclusion in the 2022 Chambers USA Guide to America's Leading Lawyers for Business , the highly regarded directory of leading attorneys and...


46 Preti Flaherty Attorneys Selected by Peers for Inclusion in Best Lawyers in America 2023, Including 6 “Lawyers of the Year”

Forty-six Preti Flaherty attorneys have been named to Best Lawyers in America 2023, including three “Ones to Watch” and six “Lawyer of the Year” recipients. Inclusion in Best Lawyers in America is considered a...


Fifteen Preti Flaherty Attorneys Selected for Inclusion in 2022 Super Lawyers

Fifteen Preti Flaherty attorneys have been selected for recognition by Super Lawyers , including seven Rising Stars. Super Lawyers rates outstanding lawyers throughout the United States in more than 70 practice areas. Only five...