Thomas A. Lorenzen

Mr. Lorenzen is a partner in Crowell & Moring's Washington, D.C. office and is a member of the Environment & Natural Resources and Government Affairs groups. He works with clients seeking to successfully navigate the federal environmental rulemaking process.

With a decade of Justice Department experience managing the legal defense of all EPA rules, Mr. Lorenzen has a unique ability to help clients shape environmental policy, provide vital input on proposed federal environmental regulations through written comment and direct interaction with regulators, and mount effective judicial challenges to EPA actions that adversely affect his clients' interests. He also helps clients ensure compliance with existing environmental regulations. In addition, he is a noted appellate lawyer who has briefed, argued, or supervised hundreds of petitions for review of EPA regulations and other final EPA actions.

While he was at the Department of Justice, Mr. Lorenzen oversaw many of the seminal environmental cases of the last decade. These include Massachusetts v. EPA, in which the Supreme Court affirmed EPA's authority to regulate greenhouse gases under the Clean Air Act, and Entergy v. Riverkeeper, in which the Court held that EPA has discretion under the Clean Water Act to consider or decline to consider costs in determining how to regulate cooling water intake structures. In the D.C. Circuit and the other federal courts of appeals, he oversaw the government's defense in Coalition for Responsible Regulation v. EPA, in which the court upheld EPA's first suite of greenhouse gas regulations (largely upheld by the Supreme Court in Utility Air Regulatory Group v. EPA); EME Homer City Generation, L.P. v. EPA and North Carolina v. EPA, in which the court reviewed EPA's various attempts to address interstate transport of air pollutants; numerous cases challenging EPA regulations governing emissions of hazardous air pollutants; and National Cotton Council v. EPA, in which the Sixth Circuit reviewed EPA's Clean Water Act regulations governing the application of pesticides over waters of the United States.

Mr. Lorenzen is a frequent lecturer and commentator in print, on the internet, and on television regarding federal environmental law, climate change regulation, administrative law, federal policymaking, and effective appellate brief-writing and argument.