John Masterson

John Masterson

Main: 307-234-6907
Licensed in: Wyoming

OverviewExperience & ResultsPractice AreasHonors & InsightsEducation & Admissions

John Masterson has played a significant part of the legal community in Wyoming and Casper for decades. His expertise and judgment are and have been relied upon by the state, its governors, and local and national businesses. He focuses his practice on the areas of Litigation, Energy and Natural Resources, Governmental Relations, Transactional Matters, and Corporate and Non-Profit Governance.

Beginning with a return to his hometown of Casper after graduation from the University of Wyoming’s College of Law, John worked for County and District Courts in Natrona County, performing legal research for judges, drafting opinions and decision letters and assisting the court in hearings and jury trials. Following his one-year term, John began three years of private practice focusing on oil and gas law, criminal defense and domestic relations.

In 1990, John became an Assistant District Attorney in Casper, with extensive experience in the prosecution and litigation of narcotics cases, domestic violence offenses, sexual assault and child exploitation. 1995 found John in the United States Attorney’s Office for the District of Wyoming, primarily responsible for the enforcement of computer crimes and crimes against children, but also prosecuting the entire spectrum of federal criminal offenses from large, multi-defendant narcotics conspiracies, to gun crimes and bank robberies to immigration offenses and wildlife crimes. During this time, John was also responsible for the training of federal and state law enforcement officers in substantive issues of law as well as interrogation, detention and search and seizure

In 2003, John was tapped by Wyoming’s newly elected Governor, Dave Freudenthal, to be the legal counsel and federal/state relations coordinator within the Governor’s Office. For two and a half years, John performed the daily legal work for the Governor and his office, participated in policy making, interagency cooperation, drafting legislation and testifying before legislative and Congressional committees. John served as the Governor’s representative for state, regional and national organizations including the Western Governors Association, the National Governors Association and the University of Wyoming Board of Trustees. For approximately six months, he served as an Interim Director of the Governor’s Planning Office.

In his final months of service to the state, John was the Deputy Director of Wyoming’s Office of State Lands and Investments, participating directly in policy making, oversight and administration of over 3.5 million acres of state surface lands and 4.2 million acres of minerals. This role led John to directly participate in negotiating, legal review and contract drafting of precedent setting state land transactions.

On returning to his hometown of Casper, John joined former Wyoming Governor and United States Ambassador to Ireland Mike Sullivan in the Wyoming office of Rothgerber Johnson & Lyons LLP. There John reentered the private practice of law, serving and representing public and private clients by providing transactional work, legislative and governmental relations, arbitration, and complex litigation in state and federal courts.

John is an active participant in the Casper community, serving on the board of six non-profits, benefitting health care, education, private grant making and young people. His volunteer service also extends to the Wyoming State Bar, where he is the Chairman of the Board of Law Examiners as well as the Bar’s current President. He also operates a family-owned ranching company and an oil and gas company.

John has extensive trial experience in federal and state courts, as well as numerous appearances before permitting, administrative and legislative hearing bodies. His appellate experience includes the Wyoming Supreme Court and the Tenth Circuit Court of Appeals

Experience & Results
  • Northern Laramie Range Foundation, et al., v. Converse County Board of County Commissioners, and Wasatch Wind Intermountain, LLC d/b/a Pioneer Windpark I, LLC, and Pioneer Windpark II, LLC, 2012 WY 158, December 14, 2012
  • Exxon Mobil Corporation v. Wyoming Oil and Gas Conservation Commission and Denbury Onshore, LLC, 2013 WY 32, March 15, 2013
  • Powder River Basin Resource Council, et al. v. Wyoming Oil and Gas Conservation Commission and Halliburton Energy Services, Inc., 2014 WY 37, March 12, 2014
  • Ultra Resources v. Hartman, 2015 WY 40, March 19, 2015
  • Hedquist v. Beamer, 763 Fed.Appx. 705, Tenth Circuit Court of Appeals, February 13, 2019
  • Black Card, LLC v. Visa U.S.A., Inc., 766 Fed.Appx. 583, Tenth Circuit Court of Appeals, March 07, 2019
Practice Areas
  • Litigation
  • Energy and Natural Resources
  • Governmental Relations
  • Nonprofit and Corporate Law
  • Oil & Gas Litigation
  • Water Rights
  • Renewable & Alternative Energy
  • Complex Commercial Litigation
  • Eminent Domain
  • Appeals
  • Mediation & Arbitration
  • Trial
Honors & Insights
  • Listed by Lawdragon as one of the “500 Leading U.S. Energy Lawyers” in 2023
  • Selected for inclusion in The Best Lawyers in America© in the fields of Energy Law, 2017-2019, 2021-2024, Natural Resources Law, 2018-2019, 2021-2024, Appellate Practice, 2018-2019, 2021-2024 and Litigation-Real Estate, 2016-2018, 2021-2024
  • Selected as a Mountain States Super Lawyer, 2016-2023
  • Recognized in the 2013-2022 editions of Chambers USA Annual Client’s Guide to Business Lawyers in the area of Litigation: General Commercial
  • Author, From the President bi-monthly column, Wyoming Lawyer Magazine, 2016 – 2017
  • Author, Beware the Budget Footnote, Wyoming Business Report, February 7, 2016
  • Governor Mead Updating Energy Strategy, Wyoming Business Report, October 6, 2015
  • Lecturer and Judge: Wyoming Summer Trial Institute, 2013-present; Wyoming High School Mock Trial Competition; WTLA Voir Dire Competition
  • Wyoming Medical Center, Board Member, Past Officer and Chair (2010 – 2019); Troopers Foundation (2008 – present); Drum Corps International (2011 – present); Tate Foundation Board Member and Officer; Masterson Family Foundation, Board Member and Chair (2002 – present); Natrona County Public Library Foundation, Board Member, Past Officer and Chair (2009 – present); Wyoming Nonprofit Network Board Member (2022-present); Drum Corps International Board Member (2012-present); University of Wyoming College of Law Advisory Board (2016-present); Natrona Collective Health Trust (2020-present)
  • President, Wyoming State Bar, 2016 – 2017
  • President Elect, Wyoming State Bar, 2015 – 2016
  • Vice President, Wyoming State Bar, 2014 – 2015
  • Board of Law Examiners, Wyoming State Bar, 2012 – 2018; 2022-present
  • Board of Professional Responsibility, Wyoming State Bar, 2018 – present
  • J.D., University of Wyoming College of Law, 1986
  • College of Literature, Science and the Arts, University of Michigan, 1983
Bar Admissions / Qualifications
  • University of Wyoming College of Law Advisory Board, 2016 – present
  • Wyoming, 1986
  • Wyoming Supreme Court, 1986
  • Wyoming State Judicial District Courts, 1986
  • U. S. District Court, Wyoming, 1986
  • U. S. Court of Appeals, Tenth Circuit, 1987