Sean R. Gallagher

Sean R. Gallagher
Firm: Polsinelli PC
Address: 1515 Wynkoop Street
Suite 600
Denver, CO 80202
Phone: 720-931-1163
Fax: 303-572-7883
E-mail: Contact Us
Web site:
Offers Free Initial Consultation
Accepts Credit Cards

Position Areas of Practice Bar Admissions
Education Honors Published Works
Lawyer Profile:

Sean Gallagher has spent more than 25 years representing clients in boardrooms and courtrooms across the country and is one of only a handful of Colorado lawyers in the history of the state to have argued a case in the Supreme Court of the United States and prevailed with a unanimous decision.

Noted by the Chambers USA guide for his "excellent follow through," Sean's practice emphasizes three general areas: complex commercial litigation, employment counseling/litigation, and constitutional/public policy matters.

His representative commercial litigation experience includes cases involving claims for common law fraud and misrepresentation, securities fraud, defamation, antitrust violations, consumer protection violations, theft of intellectual property, whistleblowing and violations of the False Claims Act, and corporate governance disputes. Sean also assists clients in implementing proactive employment policies that minimize the risk of litigation. When necessary, however, he represents senior executives and management in all aspects of employment litigation.

Sean has also handled a broad spectrum of public policy, constitutional, and election matters, including several First Amendment cases of national significance. He has served as national counsel for three presidential campaigns, has twice been appointed a Special Assistant Attorney General by the State of Colorado, and has been retained on multiple occasions by the U.S. Department of Justice to represent federal officials in civil litigation. In 2012, he successfully represented two U.S. Secret Service agents in the Supreme Court of the United States in Reichle v. Howards, 566 U.S._(2012) where he obtained a unanimous decision on behalf of his clients in a case involving the scope of civil liability of Secret Service agents protecting the President and Vice President.

As an adjunct to his litigation practice, Sean is nationally recognized for his experience in the field of electronic discovery. He is a member of The Sedona Conference's Working Group on Best Practices for Electronic Document Retention and Production and helped lead a team that drafted the conference's commentary on Proportionality in the e-Discovery Process. He has lectured extensively on litigation, ethics, and electronic discovery matters.

  • Successfully represented two U.S. Secret Service agents in the Supreme Court of the United States in a case involving the scope of civil liability of Secret Service agents protecting the U.S. President and Vice-President.
  • Successfully represented a member of the President's advance team in a case involving alleged viewpoint discrimination by the White House.
  • Successfully represented the largest private operator of health care facilities in the world in a challenge to a $1.4 billion acquisition of seven hospitals in Colorado.
  • Successfully represented a Fortune 100 corporation in litigation arising out of the failed implementation of an Enterprise Resource Planning software package.
  • Represented an agency of the state of Colorado in litigation arising out of a joint venture to develop loan portfolio management software.
  • Obtained summary judgment on behalf of client in case alleging disability discrimination.
  • Represented the Colorado governor in the state's congressional redistricting litigation following the 2000 decennial census.
  • Successfully represented a U.S. Congressman in a recount following the closest congressional race in the 2002 general election.
  • Served as Colorado general counsel and national recount counsel for Republican presidential candidates in the last three presidential campaigns.
Current Employment Position(s):

Areas of Practice:
Commercial Litigation
Labor and Employment
Bar Admissions:
Colorado, 1987
U.S. Supreme Court, 2004
U.S. Court of Appeals 10th Circuit, 1987
U.S. Court of Appeals 9th Circuit, 2003
University of Denver Sturm College of Law, Denver, Colorado, 1987

Baylor University, Waco, Texas, 1984

Published Works:
The Practitioner's Guide to Colorado Employment Law, Managing Editor, Published by Continuing Legal Education in Colorado and the Colorado Bar Association, 2012

Exploring the Often Overlooked Concept of Proportionality, The National Law Journal Gallagher & Crowley, April 11, 2011

The Sedona Conference Commentary on Proportionality in Electronic Discovery, Contributing Editor, The Secona Conference Journal, Vol. 11, Fall, 2010

Honors and Awards:
Selected for inclusion in The Best Lawyers in America®, Commercial Litigation, 2011 - 2014

Selected for inclusion in The Best Lawyers in America®, Litigation - Labor and Employment, 2011 - 2014

Selected for inclusion in Colorado Super Lawyers, 2006 - 2007

Selected for inclusion in Colorado Super Lawyers, 2009 - 2013

Ranked in the Top 100 Colorado Super Lawyers, 2013

Selected by the Denver Business Journal as one of top 10 newsmakers in the legal field for their 2012 Power Book

Chambers USA, 2004 - 2007

Denver Business Journal, Forty Under 40 Business Leaders, 2001

Professional Associations and Memberships:
American Bar Association

Colorado Bar Association

Denver Bar Association

American Bar Association
Employment Rights and Responsibilities Sub-Committee

American Bar Association
Labor Law Committee

Faculty of Federal Advocates
Board of Directors

The Sedona Conference, Working Group on Best Practices for Electronic Document Retention and Production

Colorado Bar Foundation,

Birth Information:
West Practice Categories:
Employment, Labor

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