Douglas Mackin

Member

Boston

(617) 849-5006

(857) 488-4871

Recent News:

Best Lawyers Honors More Than 200 Cozen O'Connor Attorneys in its Best Lawyers in America 2025 Edition

Best Lawyers selected 242 Cozen O’Connor lawyers from 24 of the firm’s U.S. offices for inclusion in the 2025 edition of The Best Lawyers in America and Best Lawyers: Ones to Watch in America.

Doug concentrates his practice on construction law, counseling owners, developers, contractors and subcontractors in all phases of a construction project, from contract negotiation through to completion. He routinely assists clients with claims relating to construction or design defects, change order disputes, delay/acceleration issues, mechanics' liens, bonds, and indemnity. He has experience in negotiation, mediation, and arbitration settings, including successfully prosecuting downstream claims for defective work and upstream claims for delay/accelerations claims. 

Prior to joining the firm, Doug was an associate with an Am Law 200 firm in Boston and a boutique construction firm based in Chicago. In his previous roles, Doug represented owners, contractors, and sureties in arbitration and litigation, drafted and negotiated construction contracts, developed expert reports and opinions, argued motions, and advised clients regarding ongoing construction projects. He has been involved in a wide range of projects throughout the construction industry, including education, health care, multifamily residential, energy, commercial, and infrastructure. 

Doug earned both his legal and undergraduate degrees from Washington University in St. Louis. 

Experience

News

Best Lawyers Honors More Than 200 Cozen O'Connor Attorneys in its Best Lawyers in America 2025 Edition

August 15, 2024

Best Lawyers selected 242 Cozen O’Connor lawyers from 24 of the firm’s U.S. offices for inclusion in the 2025 edition of The Best Lawyers in America and Best Lawyers: Ones to Watch in America.

Cozen O’Connor Promotes 23 Attorneys to Member

March 15, 2024

“This is a group of terrific lawyers across many offices and practices areas and we look forward to following their achievements,” said Executive Chairman and Chief Executive Officer Michael J. Heller.

Publications

Massachusetts Rules Defenses to Prompt Pay Act Violations Retained if Payment Made Before Assertion [Alert]

June 18, 2024

Douglas Mackin and Michael Filbin discuss the Massachusetts Supreme Judicial Court's recent opinion of first impression regarding the Prompt Pay Act.

Toolbox Talk Series Recap – Using a Measured Mile Analysis to Compare Productivity on a Construction Project

November 03, 2023

Douglas Mackin contributed the article to the American Bar Association Forum on Construction Law’s The Dispute Resolver, discussing productivity loss on construction projects.

Toolbox Talk Series Recap – Expert Conferencing ("Hot Tubbing") in Construction Disputes

June 02, 2023

Douglas Mackin contributed the article “Toolbox Talk Series Recap – Expert Conferencing ("Hot Tubbing") in Construction Disputes” to the American Bar Association Forum on Construction Law’s The Dispute Resolver.

Toolbox Talk Series Recap – In-House Counsel's Perspective on Improving Construction Arbitration

April 03, 2023

Douglas Mackin contributed the article “Toolbox Talk Series Recap – In-House Counsel's Perspective on Improving Construction Arbitration” to the American Bar Association Forum on Construction Law’s The Dispute Resolver.

Education

  • Washington University School of Law, J.D., 2014
  • Washington University in St. Louis, B.A., 2011

Awards & Honors

Best Lawyers in America "Ones to Watch" 2025

  • Massachusetts
  • Illinois
  • U.S. District Court -- Massachusetts
  • U.S. District Court -- Northern District of Illinois

American Bar Association Forum on Construction Law, Dispute Resolver Blog Editor 

Massachusetts Bar Association

Associated General Contractors of Massachusetts

Construction Industries of Massachusetts