O’Melveny Worldwide
  • Representing an oilfield services company in an indemnity dispute pending in Oklahoma federal court involving over US$100 million
  • Representing an American multinational conglomerate in a matter seeking pre-suit discovery in Galveston, Texas against a mass tort plaintiffs’ lawyer for use in investigating potential fraud
  • Defeated a US$275 million breach-of-contract action brought by a major oil and gas operator against a global oilfield equipment manufacturer after two-week federal bench trial. The high-stakes case for the client had significant implications for the oil and gas industry. The Fifth Circuit upheld the trial-court win. Denise was twice recognized for her work on this matter by The American Lawyer as a “Litigator of the Week” Runner-Up.
  • Defeated a global insurance provider’s petition for pre-suit discovery against a valve manufacturer in connection with an explosion at a plastics plant in south Texas involving US$65 million in insured losses and prevented the client from being sued
  • Prevailed in a federal court action to set aside a US$1.4 billion default judgment secured by a privately owned energy company against a prominent foreign national who had not been properly served with process
  • Represented an oilfield-services company in a hexavalent-chromium-contamination lawsuit brought by Texas residents after Erin Brockovich made allegations against the client on a national morning news program. Also represented the client in connection with the investigations led by the Environmental Protection Agency and Texas Commission on Environmental Quality. Secured the complete dismissal of the lawsuit when Texas’s Eastland Court of Appeals issued mandamus relief and exonerated the client at the regulatory level.
  • Represented the former owner of a sand mine located in rural Wisconsin in the defense of environmental and toxic tort claims
  • Negotiated favorable resolution of a mass-tort case involving a 20-day uncontrolled blowout of a gas well in South Texas, from which plaintiffs alleged there was a discharge of toxic hydrocarbons and carcinogenic gases that produced an environmental hazard damaging thousands of acres of property, surrounding waterways, livestock, and the plaintiffs’ health
  • In a landmark case that included a four-week federal court trial, two Fifth Circuit rulings, and an eight-page statement from the US Supreme Court, Denise was part of a team that secured the United States’ first permanent injunction requiring a prison to provide robust COVID-19 protections—including testing all inmates on a weekly basis—for a geriatric prisoner in Texas, earning the team a National Law Journal “Trailblazer Award for Crisis Leadership.”

Admissions

Bar Admissions

  • Texas

Education

  • Southern Methodist University, J.D., 1992
  • Vanderbilt University, B.A., 1989

Honors & Awards

  • Recognized as a “Leading Partner” by The Legal 500 US in General Commercial Disputes (2021-2026)
  • Recommended by The Legal 500 US in Energy Transactions: Oil and Gas (2025-2026)
  • Recognized by Chambers USA for Litigation: General Commercial (2025-2026)
  • Recognized by Best Lawyers in America for Commercial Litigation, Litigation - Environmental, Mass Tort Litigation / Class Actions - Defendants, Oil and Gas Law, and Personal Injury Litigation - Defendants in Houston, TX (2022-2026)
  • Recommended by The Legal 500 US in: Product Liability, Mass Tort, and Class Action – Defense: Toxic Tort (2021-2024) and Energy Litigation: Oil and Gas (2021, 2023, 2024)
  • Lawdragon: “500 Leading Litigators in America” for Commercial Litigation, Mass Tort, and Toxic Torts (2024-2026); “The Green 500: Leaders in Environmental Law” (2024-2025); “500 Leading Environmental Lawyers” (2023); “500 Leading Energy Lawyers” (2023-2025); and “500 Leading Environmental and Energy Lawyers” (2021)
  • Texas Lawyer’s Texas Legal Awards, “Best Mentor” (2022)

Professional Activities

Affiliations

  • Past-President, Houston Bar Association
  • Director, Texas Access to Justice Foundation
  • Past Chair and Trustee, Houston Bar Foundation
  • Director, Houston Urban Debate League
  • Past Director, State Bar of Texas
  • Life Fellow, Houston Bar Foundation
  • Fellow, Texas Bar Foundation

Speaking Engagements

  • “Crisis Management and Emergency Response: Best Practices in the Energy Industry,” The Texas Journal of Oil, Gas, and Energy Law Symposium, Feb. 2023
  • “The Past, Present and Future of Women in the Law,” Houston Bar Association Seminar, April 2021