Former Acting Assistant Attorney General, United States Department of Justice; Partner, Winston & Strawn LLP
Jonathan “Jon” Brightbill is a trial and appellate lawyer in Winston’s Washington, D.C. office, and a partner in the firm’s Litigation and White Collar, Regulatory Defense, and Investigations Practices. He represents public and private companies, corporate officers, and other individuals across white collar, regulatory defense, and government and internal investigation matters and rulemaking challenges, as well as complex commercial disputes, citizen suits, and class actions. His commercial litigation experience encompasses business disputes, false advertising, consumer protection and fraud, FCA, and extensive class action defense work; antitrust and unfair competition matters; and intellectual property litigation, such as trademarks, patents, and trade secrets.
Jon served as the Nation’s lead environmental civil and criminal enforcement official and litigator, as Acting Assistant Attorney General for the Environment & Natural Resources Division (“ENRD”) of the U.S. Department of Justice (DOJ). Jon led ENRD’s 425 lawyers, overseeing 6,500 active matters and managing an annual budget of more than $150 million. Jon brings highly experienced executive leadership from among the most senior level of DOJ on white collar and regulatory enforcement, as well as on federal policymaking and rulemaking development and challenges. He speaks with authority on government decision-making processes, and the arguments and perspectives that move regulators and enforcers, best advising and positioning clients to deal with challenges.
Jon argued many of the government’s most significant cases during his time with the DOJ. This included the Navigable Waters Protection Rule and Clean Water Rule Repeal (10th Cir., district courts), the Affordable Clean Energy Rule and Clean Power Plan Repeal (D.C. Cir), defense of EPA actions on pesticide tolerances under FIFRA and the FDCA (9th Cir. en banc), among numerous others. Jon represented the United States in trial courts in both enforcement and defensive cases, including federal enforcement action against Jeffrey Lowe and the Tiger King Park, of Netflix fame, securing a first-of-its-kind injunction for violations of the Endangered Species Act and Animal Welfare Act. Jon directed the litigation and briefing of scores of additional federal cases nationwide, covering all of the major environmental and natural resources statutes, such as the Clean Air Act, the Clean Water Act, FIFRA (pesticides), FDCA (food safety), TSCA (toxics), CERCLA (land remediation), RCRA (waste), National Environmental Policy Act, Federal Land Policy and Management Act, and numerous other land- and resource-management statutes.
Jon has unmatched experience litigating legal and technical issues relating to climate change. He argued in the courts of appeals, including the D.C. Circuit, regarding the most significant climate change regulations by EPA, as well as the preemptive scope of the Clean Air Act. Jon also litigated climate change-related credit and trading schemes and international agreements in district court. During Jon’s time in leadership at ENRD, it successfully defeated one of the most wide-ranging lawsuits regarding climate change to date—obtaining a stay pending interlocutory appeal and dismissal just weeks before a scheduled three-month trial on federal government liability for climate change.
An accomplished trial lawyer, prior to working at DOJ, Jon was a partner in the Washington, D.C. office of another global law firm. He not only represents clients in court, but creatively counsels corporations on balancing business needs and realities with a broad range of litigation risks and compliance obligations. Jon is also an Adjunct Professor at Georgetown University Law Center. He served on the American Bar Association’s E-Discovery Working Group for Bankruptcy Practice, and was a frequent lecturer for District of Columbia Bar Association Continuing Legal Education Programs.
Jon served as an appellate clerk for the Honorable D. Brooks Smith, U.S. Court of Appeals for the Third Circuit, after graduating magna cum laude from the Georgetown University Law Center. He worked in state government as an Executive Policy Specialist for air, waste, land remediation, and radiation matters at the Pennsylvania Department of Environmental Protection.
Laurence A. Tisch Professor of Law and Director, Classical Liberal Institute, New York University School of Law; Senior Fellow, The Civitas Institute, University of Texas at Austin
Richard A. Epstein is the inaugural Laurence A. Tisch Professor of Law at NYU School of Law. Prior to his joining the faculty, he was a visiting law professor at NYU from 2007 through 2009. He served as the Peter and Kirstin Bedford Senior Fellow at the Hoover Institution from 2000 to 2024. Since 2024 to the present he is a senior lecturer at the Civitas Institute at the University of Texas—Austin. Epstein is also the James Parker Hall Distinguished Service Professor of Law Emeritus and a senior lecturer at the University of Chicago. His initial law school appointment was at the University of Southern California from 1968 to 1972. Epstein received an LL.D., h.c. from the University of Ghent, 2003. He has been a member of the American Academy of Arts and Sciences since 1985 and was a Senior Fellow of the Center for Clinical Medical Ethics at the University of Chicago Division of Biological Sciences, also from 1983. to 2022 He served as editor of the Journal of Legal Studies from 1981 to 1991, and of the Journal of Law and Economics from 1991-2001. From 2001 to 2010 he was a director of the John M. Olin Program in Law and Economics at the University of Chicago.
His newest book, The Myth of Birthright Citizenship: What the Fourteenth Amendment Really Says was published in 2026 (Encounter Books). Prior to that he has published many books including, The Dubious Morality of the Modern Administrative State (Roman & Littlefield 2020).Earlier he published th Classical Liberal Constitution: The Uncertain Quest for Limited Government (Harvard 2014) iHis previous books include Design for Liberty: Private Property, Public Administration and the Rule of Law (Harvard 2011); The Case Against the Employee Free Choice Act (Hoover 2009); Supreme Neglect: How to Revive the Constitutional Protection of Property Rights (Oxford 2008); Antitrust Decrees in Theory and Practice: Why Less is More (AEI 2007); Overdose: How Excessive Government Regulation Stifles Pharmaceutical Innovation (Yale University Press. 2006); How Progressives Rewrote the Constitution (Cato 2006); Cases and Materials on Torts (Aspen Law & Business; 8th ed. 2004); Skepticism and Freedom: A Modern Case for Classical Liberalism (University of Chicago, 2003); Torts (Aspen Law & Business 1999); Principles for a Free Society: Reconciling Individual Liberty with the Common Good (Perseus Books, 1998): Mortal Peril: Our Inalienable Rights to Health Care (Addison-Wesley, 1997); Simple Rules for a Complex World (Harvard, 1995); Bargaining With the State (Princeton, 1993); Forbidden Grounds: The Case Against Employment Discrimination Laws (Harvard , 1992); Takings: Private Property and the Power of Eminent Domain (Harvard, 1985); and Modern Products Liability Law (Greenwood Press, 1980). He has also edited(with Catherine M. Sharkey) Cases and Materials on the Law of Torts (10th edition 2012).
Professor Epstein has written numerous articles on a wide range of legal and interdisciplinary subjects. He has taught courses in administrative law, antitrust law, civil procedure, communications, constitutional law, contracts, corporations, criminal law, employment discrimination law, environmental law, food and drug law health law and policy, legal history, labor law, property, real estate development and finance, jurisprudence, labor law; land use planning, patents, individual, estate and corporate taxation, Roman Law; torts, and workers' compensation.
Professor Epstein also writes a regular column for Civitas Institute, which also sponsors his podcast, The Libertarian with Charles C.W. Cooke, and Law Talk, with Cooke and John Yoo. He also does a podcast with John Batchelor. And appears regularly on the Freedom File with Judge Andrew Napolitano.
Emmett Visiting Assistant Clinical Professor of Law in Environmental Law, Harvard Law School
Andrew Mergen is a Visiting Assistant Clinical Professor of Law and Faculty Director of the Emmett Environmental Law & Policy Clinic. Prior to joining the Harvard Law School faculty, Andrew Mergen served in the Appellate Section of the Environment & Natural Resources Division (ENRD) at the United States Department of Justice. Professor Mergen began his career at the Justice Department in the Honors Program and concluded his career as Chief of ENRD’s Appellate Section. He has presented oral arguments in all 13 federal courts of appeals, including two en banc courts, and before several state intermediate and supreme courts. He has also worked on over a dozen merits cases in the Supreme Court of the United States. In addition, in 2009, Professor Mergen assisted the Office of White House Counsel on the confirmation of the Honorable Sonia Sotomayor as Associate Justice of the Supreme Court. During his career at the Justice Department, Professor Mergen received the Attorney General’s Award for Distinguished Service three times. He also received ENRD’s Muskee-Chafee Award, honoring his work’s significant contribution to protecting the environment.
Before entering clinical teaching, Professor Mergen taught at several law schools including, Harvard Law School (Advanced Environmental Law), the University of Michigan Law School (Natural Resources Law) and the William S. Richardson School of Law, University of Hawaii-Manoa (Administrative Law). Professor Mergen has written about federal water rights in “A Misplaced Sensitivity: The Draft Opinions in Wyoming v. United States” (68 Colo. L. Rev. 683 (1997), with Sylvia F. Liu); energy development on public lands in “Surface Tension: The Problem of Federal Private Split Estates” (33 Land & Water L. Rev. 419 (1998)); climate change and the Endangered Species Act in “The Role of Climate Change in ESA Listing Decisions” (53 Rocky Mt. Min. L. Fdn. 67 (2016), with Murray Feldman) and the accommodation of Native American sacred sites on federal land in “Finding the Path Forward for Indigenous Sacred and Cultural Spaces on Federal Public Land,” 68 Nat. Resources & Energy L. Inst. 32-1 (2022). Professor Mergen is a graduate of the University of Wisconsin—Madison and the George Washington University Law School.
Robert F. Stanton Professor of Law, University of Maryland Carey School of Law
Robert V. Percival is the Robert F. Stanton Professor of Law and the Director of the Environmental Law Program at the University of Maryland School of Law. He received a B.A. summa cum laude from Macalester College, a J.D. from Stanford Law School and an M.A. in economics from Stanford University. At Stanford Percival was named the Nathan Abbott Scholar for graduating first in his law school class. Following graduation, he served as a law clerk for Judge Shirley M. Hufstedler of the U.S. Court of Appeals for the Ninth Circuit and for U.S. Supreme Court Justice Byron R. White. He joined the Maryland faculty in 1987 after serving as a senior attorney for the Environmental Defense Fund. Percival has served as a visiting professor of law at Harvard Law School, Georgetown University Law Center, the China University of Political Science and Law (Beijing), and Comenius University (Bratislava). He is the principal author of a leading environmental law casebook, now in its 9th edition, and the author of several articles about the Supreme Court and presidential authority over executive agencies. Percival wrote one of the first articles on the propriety of consent decrees to effectuate and enforce federal law “The Bounds of Consent: Consent Decrees, Settlements and Federal Environmental Policymaking,” 1987 Univ. Chic. Leg. F. 327 (1987). He also is the author of the first comprehensive analyses of what the papers of the late Justices Thurgood Marshall and Harry Blackmun reveal about the Supreme Court’s handling of environmental cases (“Environmental Law in the Supreme Court: Highlights from the Blackmun Papers,” 35 ELR 10637 (2005), and “Environmental Law in the Supreme Court: Highlights from the Marshall Papers,” 13 ELR 10606 (Oct. 1993)).
Judge, U.S. Court of Appeals for the Third Circuit
Hon. Jennifer Mascott served as Associate Professor of Law and Director of the Separation of Powers Institute at The Catholic University of America’s Columbus School of Law before her appointment to the federal bench. On July 16, 2025, President Donald J. Trump nominated her to the U.S. Court of Appeals for the Third Circuit (Delaware), and she was confirmed on October 9, 2025.
Prior to her confirmation, Judge Mascott wrote extensively in administrative and constitutional law, statutory interpretation, and the separation of powers. Her scholarship—published in leading journals including the Stanford Law Review, Notre Dame Law Review, and Supreme Court Review—was cited by the U.S. Supreme Court and multiple federal courts. She also contributed Supreme Court commentary for NBC Universal.
Before joining Catholic Law, she was an Assistant Professor and Co-Director of The C. Boyden Gray Center at George Mason University’s Antonin Scalia Law School. In 2022 she became co-author of Beermann, Cass & Diver’s Administrative Law: Cases and Materials (9th ed.). In 2023 she received the Justice Joseph Story Award for excellence in scholarship, teaching, and advancing the rule of law.
Judge Mascott also served as a Council Member of the ABA’s Administrative Law Section and as a Public Member of the Administrative Conference of the United States. She frequently testified before Congress on executive power, regulatory reform, and judicial jurisdiction, and participated in multiple Supreme Court confirmation hearings.
From 2019 to 2021, she took leave from academia to serve as Deputy Assistant Attorney General in the Department of Justice’s Office of Legal Counsel and later as Associate Deputy Attorney General, where she argued federal cases and assisted with Justice Amy Coney Barrett’s confirmation. Earlier in her career, she clerked for Justice Clarence Thomas and for then-Judge Brett M. Kavanaugh on the D.C. Circuit.
Judge Mascott earned her J.D. summa cum laude from the George Washington University Law School and her B.A. from the same institution.
Judge, United States Court of Appeals, Third Circuit
Judge Paul Matey was appointed to the United States Court of Appeals for the Third Circuit in 2019 by President Trump.
Before his judicial service, Judge Matey was a partner at Lowenstein Sandler in New Jersey where he practiced complex commercial litigation and criminal defense. Earlier, Judge Matey was the Senior Vice President, General Counsel and Secretary for University Hospital Newark, an academic medical center and teaching hospital.
He also served as the Deputy Chief Counsel to Governor Chris Christie, and as an Assistant United States Attorney in the District of New Jersey, where he was awarded the Justice Department’s Director’s Award for Superior Performance. He also practiced at the Washington D.C. firm of Kellogg, Hansen, Todd, Figel & Frederick, and served as a law clerk to judges on the United States Court of Appeals for the Third Circuit and the United States District Court for the District of New Jersey.
He earned his bachelor’s degree from the University of Scranton, a Jesuit University, in 1993, and his juris doctorate, summa cum laude, from Seton Hall University School of Law in 2001, where he served as Editor-in-Chief of the Seton Hall Law Review.
In 2019, Judge Matey was elected to membership in the American Law Institute and, since 2020, has lectured on administrative law and the American legal history at Seton Hall.
Adjunct Professor, George Washington University Law School
Professor of Law, University of Michigan Law School
Christopher J. Walker is a Professor of Law at the University of Michigan. Prior to joining Michigan law faculty in 2022, he spent a decade teaching at The Ohio State University Moritz College of Law. He previously clerked for Justice Anthony Kennedy of the U.S. Supreme Court, worked on the Civil Appellate Staff at the U.S. Department of Justice, and served on the Senate Judiciary Committee staff for the Gorsuch Supreme Court confirmation. Professor Walker’s research focuses on administrative law, regulation, and law and policy at the agency level. Outside the law school, he chaired the American Bar Association’s Section of Administrative Law and Regulatory Practice in 2020-21 and served as one of forty Public Members of the Administrative Conference of the United States from 2016-2022, and he continues to serve in both organizations in various capacities. He also works of counsel at the U.S. Chamber Litigation Center. In 2022, he received the Federalist Society’s Joseph Story Award.
Chief Legal Officer and Policy Director, Cicero Institute
Jonathan Wolfson is the Chief Legal Officer and Policy Director at the Cicero Institute. Before joining Cicero, he led the Policy Office at the U.S. Department of Labor where he managed DOL's deregulatory efforts and oversaw DOL's internal policy development think tank. He previously was a litigator and regulatory attorney at an international law firm representing clients before state and federal courts across the country. Following law school he served as a law clerk to The Honorable Edith Brown Clement of the U.S. Court of Appeals for the Fifth Circuit. Before law school, Jonathan was a policy analyst at the White House Council of Economic Advisers.
Jonathan received an A.B. in Economics from Washington University in St. Louis and a J.D. from the University of Virginia School of Law, where he was an Olin Law and Economic Fellow and won the John M. Olin Prize for best original law and economics research.
General Counsel, Arizona Chamber of Commerce & Industry
Michael G. Bailey is currently the general counsel at the Arizona Chamber of Commerce and a partner at Tully Bailey LLP. He formerly served as the U.S. Attorney for the District of Arizona and as chief deputy in the Arizona Attorney General's Office.
Former General Counsel of the U.S. Immigration and Naturalization, Former United States Ambassador to East Timor
Grover Joseph Rees is a Louisiana native whose family has lived in the Breaux Bridge/Lafayette area since the 1700s.
His first job after college was as an assistant to Congressman Dave Treen (R-LA3), who had just been elected as the first Republican Congressman from Louisiana since Reconstruction.
Rees graduated with honors from LSU Law School, where he served as Editor-in-Chief of the Louisiana Law Review. While in law school he worked on Ronald Reagan’s 1976 presidential campaign and was a Reagan delegate from Louisiana to the Republican National Convention. He also served as a member of the Lafayette Parish Republican Executive Committee and as a board member of Acadiana Right to Life.
In 1979, when Congressman Treen ran successfully for Governor, he asked Rees to write his authorized biography. The book, Dave Treen of Louisiana, was read and discussed widely during the campaign and after Treen’s election.
In 1985-86 Rees served as Special Counsel for Judicial Selection in President Reagan’s Justice Department, working closely with Attorney General Ed Meese to reorganize the judicial selection process to make it more philosophically oriented. These efforts resulted in the appointment of over 100 federal judges and were widely credited with transforming the federal judiciary.
From 1986 through 1991 Rees served as Chief Justice of the High Court of American Samoa, an Article I federal judicial position.
From 1991 through 1993 he was General Counsel of the U.S. Immigration and Naturalization Service.
In 1995 Rees went to work for the new Republican Congress as staff director and chief counsel of the Subcommittee on International Operations and Human Rights. He worked with subcommittee chairman Chris Smith (R.-N.J.) to cut U.S. funding for the International Planned Parenthood Federation and other organizations that perform and promote abortions overseas. Rees also worked on the drafting and enactment of the International Religious Freedom Act, the Trafficking Victims Protection Act, and other legislation that has helped to bring U.S. foreign policy into closer alignment not only with our national interests but also with our values.
In 2001-2002 Rees worked for Congressman Henry Hyde (R.-Ill.), who was then serving as Chairman of the House International Relations Committee.
From 2002 until 2006 Rees served as the first United States Ambassador to newly independent East Timor.
From 2006 until 2009 Ambassador Rees was the United States Special Representative for Social Issues, responsible for representing the United States on issues relating to vulnerable persons and the family within the United Nations system.
Ambassador Rees retired from government service in January 2009 and returned to Lafayette. He is married to Lan Dai Nguyen Rees and is a member of St. Genevieve’s Catholic parish in Lafayette. He was recently elected to serve as a member of the Louisiana Republican State Central Committee.
Professor of Law, Antonin Scalia Law School, George Mason University
Adam Mossoff is Professor of Law at Antonin Scalia Law School, George Mason University. He has published extensively on why patents, copyrights, and other intellectual property rights have been—and should be—legally secured to innovators and creators as property rights. His scholarship has been relied on by the United States Supreme Court, by lower federal courts, and by U.S. federal agencies. He has been invited to testify numerous times before the U.S. Senate and the House of Representatives on intellectual property legislation. His writings on intellectual property policy have also appeared in the Wall Street Journal, New York Times, Forbes, Investors Business Daily, and in other media outlets. His journal articles can be downloaded here.
Professor Mossoff is a longstanding member of the Executive Committee of the Intellectual Property Practice Group of the Federalist Society, on which he served as Chairperson from 2016-2018, and he is Chair of the Intellectual Property Working Group of the Regulatory Transparency Project of the Federalist Society. He is a Senior Fellow and Chair of the Forum for Intellectual Property at the Hudson Institute, a Visiting Intellectual Property Fellow at the Heritage Foundation, and a member of the Board of Directors of the Center for Intellectual Property Understanding. He is a member of the Intellectual Property Rights Policy Committee of ANSI and he has served as Chair and Vice-Chair of the Intellectual Property Committee of the IEEE-USA, on which he remains a member in good standing.
Senior Policy Advisor, Speaker Nancy Pelosi
Wendell Primus is the Senior Policy Advisor on Budget and Health Issues to Speaker Nancy Pelosi. In that capacity, he was the lead staffer in developing the Affordable Care Act. He also played a major role in the SGR legislation in 2015 and various budget agreements. Prior to this appointment in March, 2005, Dr. Primus was the Minority Staff Director at the Joint Economic Committee. He has also held positions at the Center on Budget and Policy Priorities, served in the Clinton Administration at the Department of Health and Human Services and also served as Chief Economist for the House Ways and Means Committee and Staff Director for the Committee's Subcommittee on Human Resources. Dr. Primus received his Ph.D. in economics from Iowa State University.
Executive Vice President, The Federalist Society
Dean Reuter is Executive Vice President at the Federalist Society for Law and Public Policy Studies. He has served in two federal government agency Offices of the Inspector General, as Counsel to the Inspector General and Deputy Inspector General, responsible for policing the use of federal funds granted and contracted through those agencies. As such, he helped conduct and oversee criminal investigations across the country. He is the principal author of the non-fiction book, The Hidden Nazi: The Untold Story of America's Deal with the Devil, and editor of Liberty’s Nemesis: The Unchecked Expansion of the State and Confronting Terror: 9/11 and the Future of American National Security. He was appointed by the President and served as Vice-Chairman of the Board of Directors of the Corporation for National and Community Service, and recently served as an appointee on the U.S. Commission on Presidential Scholars. He is a graduate of Hood College (BA with Honors) and the University of Maryland School of Law.
Vice President, Practice Groups, The Federalist Society
Attorney Specializing in Government Relations
Alec D. Rogers is an attorney specializing in government practice and policy in Washington, DC.
A graduate of James Madison College at Michigan State University and the University of Michigan Law School, he practiced law for several years before spending over a decade on Capitol Hill as a staffer to various Members and Committees.
He has reviewed books for the Washington Times, Hardball Times, The Journal of the American Revolution, and The Weekly Standard, and writes on legal matters in Engage, an online publication of the Federalist Society.
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Courthouse Steps Oral Argument Teleforum: Sanchez v. Mayorkas
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International Reference Pricing and Negotiation: Yes or No?
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House Subcommittee Hears On Need for Fair Warning on Agency Action
Alec D. Rogers
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