vCard

Mitchell J. Klein

Of Counsel
Biography

Mitchell Klein resolves complicated environmental disputes. His background as a prosecutor and government trial attorney gives him unique insight into the objectives and strategies employed by government regulators, and his creative approaches typically allow his clients to obtain beneficial resolutions to their problems without large transactional costs.

Mitchell’s reputation for honesty and fairness helps make governmental regulators and attorneys willing to work with him to explore creative solutions, and his reputation for an aggressive and dogged defense serves as the counterweight that helps his clients achieve their goals.

With 30 years of trial experience, Mitchell counsels clients in a wide variety of environmental and natural resource legal issues. He has extensive experience working with many state and federal agencies in all areas of natural resource and environmental law. Mitchell’s experience also includes litigation pursuant to the Clean Water Act, the Clean Air Act, Hazardous and Solid Waste regulations, and Superfund liability. He represents clients with administrative, permitting, and corporate compliance issues.

Prior to re-entering private practice, Mitchell was an assistant attorney general for the State of Arizona for nearly ten years during which time he served as chief counsel for the Civil Unit of the Environmental Enforcement Section and was responsible for all environmental enforcement actions taken by the state. Mitchell is a judge pro tempore for the Maricopa County Superior Court.

Credentials

Bar Admissions

  • Arizona


Court Admissions

  • Supreme Court of Arizona
  • United States Court of Federal Claims
  • United States District Court, District of Arizona


Education

  • University of Illinois College of Law (J.D.)
  • University of Illinois (B.A.)
Experience

Awards & Recognition

  • The Best Lawyers in America®, Environmental Law (2019-2025); Natural Resources Law (2025)
  • Chambers USA: America’s Leading Lawyers for Business®, Environment (including water rights) (2014-2024)
  • Arizona’s Top Lawyers, Environmental Law, Arizona Business Magazine (2013)

Representative Experience

Air Enforcement

  • Represented food manufacturer in Oregon regarding $2,000,000 demand
  • Represented Arizona utility regarding a potential criminal liability

Water Enforcement

  • Represented Arizona mining company in connection with threatened shutdown
  • Represented Indian facility with audit and self-reporting issues

Waste Enforcement

  • Represented Arizona manufacturer regarding RCRA claims

CERCLA

  • Represented national railroad in connection with contribution claims
  • Represented California mining company in efforts to obtain contribution
  • Represented various mining manufacturing and utility companies in CERCLA litigation in California, Arizona, New Mexico, and Colorado

Previous Professional Experience

  • Polsinelli PC, Shareholder
  • Bryan Cave, Counsel
  • Jacoby and Meyers, Arizona Managing Partner
  • State of Arizona, Assistant Attorney General

Professional Memberships and Activities

  • Arizona State Bar Association
    • Environment and Natural Resources Section, Past President
  • Judge Pro Tempore, Maricopa County Superior Court

Community Involvement

  • Keep Arizona Beautiful
    • Board Member
    • Vice Chairman
  • Maricopa Parks and Trails Foundation
    • Vice Chairman
  • Arizona Strategic Alliance
    • Advisory Board Member

Representative Presentations and Publications

  • What Will EPA Do with Its New Superfund Money?” Author, Snell & Wilmer Environmental, Natural Resources, Oil and Gas Law Blog (September 23, 2021)
  • The Rush is On for Jurisdictional Determinations,” Author, Snell & Wilmer Environmental, Natural Resources, Oil and Gas Law Blog (September 14, 2020)
  • Plaintiffs Seeking to Expand Scope of PFA’s Actions,” Author, S&W Environmental, Natural Resources, Oil and Gas Law Blog (February 26,2020)
  • Disposal Of Contamination: Be Careful What You Throw Away,” Author, Law360 (June 8, 2017)
  • Trump’s EPA: Be Careful What You Wish For,” Author, Law360 (January 19, 2017)
  • “Defense Attorney Perspective,” Speaker, Western States Project, San Diego, California (September 2016)
  • “Public Records Requests,” Speaker, Arizona Manufacturers Council, ESS 2016, Prescott, Arizona (August 2016)
  • “The Defense Perspective,” Speaker, Western States Project, Mesa, Arizona (February 2016)
  • “Responding to Environmental Enforcement Actions,” Speaker, Pinal County Air Quality, Florence, Arizona (January 2016)
  • “Clean Water Act,” Speaker, Arizona State University, Tempe, Arizona (September 2015)
  • “Water Rights in Arizona,” Speaker, NBI, Phoenix, Arizona (August 2015)
  • “Lawyers, Consultants and Clients: Ethical Issues'” Speaker, Arizona Manufacturers Council, ESS 2015, Prescott, Arizona (August 2015)
  • “The Defense Perspective,” Speaker, Western States Project, Seattle, Washington (April 2015)
  • “What to Expect From, and How to Prepare for, Environmental Litigation'” Speaker, 2015 Gatekeeper Regulatory Roundup Conference, Scottsdale, Arizona (February 2015)
  • “Introduction to Criminal Environmental Investigations Course,” Speaker, Western States Project, Garden Grove, California (September 2014)
  • “How To Get The Attention of Regulators,” Speaker, Air Quality Compliance Seminar, Arizona Strategic Alliance, Phoenix, Arizona, University Club (June 2014)
  • “The Defense Perspective,” Speaker, Quadrennial Conference on Criminal Environmental Enforcement, Western States Project, San Diego, California, Bahia Hotel (May 2014)
  • “Natural Resource Damages,” Speaker, Gatekeeper Conference, Scottsdale, Arizona, Chaparral Suites Hotel (February 2014)
  • “Ethical Issues In Water Law,” Speaker, NBI, Phoenix, Arizona, Downtown Hyatt (November 2013)
  • “Resolving TRI Enforcement Cases,” Speaker, Gatekeeper Conference, Scottsdale, Arizona, Chaparral Suites Hotel (February 2013)
  • “Big Brother is Here – and watching you,” Speaker, Arizona Manufacturers Council, Prescott, Arizona, Sheraton Hotel (August 2012)