Douglas B. Tumminello

Douglas B. Tumminello

Partner vCard
303.628.9507 office
303.623.9222 fax
1200 Seventeenth Street
Suite 3000
Denver, CO 80202

Doug Tumminello’s practice focuses on complex business, business tort, and intellectual property litigation, including matters ‎involving claims against consumer product companies, recreational service providers and outdoor recreation companies. He represents a ‎variety of well-known business and non-profit entities as litigation and ‎trial counsel and has tried cases in the state and federal courts of Colorado and Wyoming as well as in ‎private arbitrations, and has argued before Colorado and federal ‎courts of appeal. Doug’s litigation experience includes product liability, negligence and intentional acts, supply chain, intellectual property, waiver/exculpatory contracts, and insurance-related claims. Doug regularly advises businesses concerning formation, corporate governance and compliance, risk management and strategic planning issues.

Doug is the Vice-Chair of the Colorado Bar Association’s Military & Veterans Affairs Section and chair’s the section’s monthly pro bono legal clinic “Colorado Lawyers for Colorado Veterans.” The clinic serves the various legal requirements of indigent military veterans throughout Colorado by pairing the veterans with attorneys willing to work on a pro bono or needs-based basis. 

Doug is also an extreme adventurer who has summited Mt. Everest ‎and set world records for rowing a row boat 3,600 miles across the ‎Indian Ocean from Australia to Mauritius. Most recently he attempted to ski solo and unsupported from the coast of Antarctica to the South Pole, although his attempt was thwarted by weather and injury. He is a well-regarded ‎national speaker and has given a number of keynote addresses to ‎business, civic and nonprofit organizations, schools and churches.

Professional Experience

  • Lewis Roca Rothgerber Christie LLP (legacy firm Rothgerber Johnson & Lyons LLP), 1996-Present
  • United States Army, Infantry Officer, 1987-1992

Representative Matters

  • Colorado counsel for Russian natural resources company in connection with lawsuits over Russian mining diamond rights. Represented client at all levels of the Colorado court system, as well as in the US District Court and Bankruptcy Court in Colorado.
  • Trial counsel for client regarding contract claims. At trial, successfully defended the claims brought against his client and prevailed on all counterclaims against the plaintiff, resulting in a $7.6 million trial judgment in favor of his client
  • Litigation counsel for a national real estate investment company, defending claims of asbestos exposure at an apartment complex. Successfully defended the claims brought by over 150 plaintiffs, which the plaintiffs estimated to be in excess of $24 million, and obtained a complete summary judgment dismissal of all claims
  • Trial counsel for a national company in a private arbitration over breach of contract and business tort claims. At arbitration, prevailed on all of the claims brought against his client, and on his client’s counterclaims against the plaintiff, which then resulted in a settlement favorable to his client
  • Trial counsel for an insurance holding company and its subsidiaries in bad faith and breach of contract lawsuits in Colorado and Wyoming federal and state courts
  • Litigation counsel for client in connection with cold weather injury claims sustained during wilderness therapy program
  • Litigation counsel for national ski resort company in business tort claims resulting from real estate development

Related News

Pro bono service awards presented by Lewis Roca Rothgerber Christie
Annual awards honor memory of lawyer dedicated to equal justice and professionalism


  • Presenter, Keynote presentation, National State Auditors Association, June 15, 2016
  • Speaker, Commencement Address, Steamboat Springs High School, June 4, 2016
  • Speaker, “Emerging Corporate Compliance Trends & Predictions,” Association of Corporate Counsel , April 20, 2016
  • Presenter, “Intellectual Property, Manufacturing and Sales Warranties, and Liability Waivers in the Outdoor Manufacturing and Services Industry,” Yampa Valley Entrepreneurship Center, March 25, 2016
  • Presenter, Keynote presentation, Medtronic, Inc. sales team, 2015
  • Presenter, Keynote presentation, IMA Financial Group, 2015

Related Publications

  • Author, "Pretrial Publicity in Criminal Cases of National Notoriety," 46 Am. U. L. Rev. 39 (1996)

To read more about Doug, click on the links below:

Other Info


Sports & Recreation Blog


J.D., University of Denver, Sturm College of Law, 1996, Order of St. Ives
B.S., United States Military Academy, West Point, 1987

Bar Admissions

Colorado, 1996
Wyoming, 2016

Court Admissions

U.S. Supreme Court
U.S. District Court, Colorado
U.S. District Court, Wyoming
U.S. Court of Appeals, Tenth Circuit
Colorado State Judicial District Courts
Colorado Supreme Court
Colorado Court of Appeals
Wyoming State Courts
Wyoming Supreme Court

Memberships & Affiliations

  • Sherpa Memorial Foundation, Board of Directors and President
  • Himalayan Rescue Association USA, Board of Directors
  • Yampa Valley Gives, Board of Directors
  • Faculty of Federal Advocates, Board of Directors
  • Military & Veterans Affairs Section Colorado Bar Association, Vice-Chair
  • Denver, Northwestern Colorado, Colorado and American Bar Associations, Member
  • 14th Judicial District, Colorado, Judicial Performance Commission
  • City of Steamboat Springs, Colorado, Parks and Recreation Commission