Ruth Mason

  • Edwin S. Cohen Distinguished Professor of Law and Taxation
  • Class of 1941 Research Professor of Law
  • Director, Virginia Center for Tax Law

Ruth Mason joined the University of Virginia School of Law faculty in 2013.

Her research focuses on federalism and the dormant Commerce Clause and cross-border taxation. Mason’s work on comparative fiscal federalism has been cited by the U.S. Supreme Court and in an advocate general’s opinion for the Court of Justice of the European Union.

A recipient of the University Research Award, Mason’s articles are forthcoming or have appeared in top U.S. law reviews, including the Yale Law Journal, California Law Review, Duke Law Review, NYU Law Review and Virginia Law Review, as well as top peer-reviewed specialty journals, including the Tax Law Review and British Tax Review. Mason also has contributed to Foreign Affairs and regularly contributes to Tax Notes. The chair lecture she gave on being named the Edwin S. Cohen Distinguished Professor of Law and Taxation at UVA was published in the American Journal of International Law and accompanied by an online symposium organized by AJIL Unbound.  

Mason lectures on tax topics around the world. She delivered the 2023 IFA Canada Lecture, on the topic of EU state aid. She also delivered the 2018 Amsterdam Distinguished Lecture in Taxation, which will be published in the Oxford Yearbook of European Law. She has been a visiting professor at several institutions, including Yale Law School, the University of Paris (Panthéon-Sorbonne), the Vienna University of Economics and the Business and the International Bureau of Fiscal Documentation. Mason has served as national reporter for the United States to the International Fiscal Association (IFA), and she is a member of the American Law Institute.

Mason supervises doctoral students, teaches taxation and serves as faculty adviser to UVA’s tax moot court team, which has won three international championships. She co-founded and co-hosts the Oxford-Virginia Legal Dialogs, an online seminar series that is open to the public and dedicated to forging ties between tax and other legal disciplines. In 2023, she was named faculty director of the Virginia Center for Tax Law.

 

Education

  • J.D.
    Harvard Law School
    2001
  • B.A.
    Columbia University
    1997

Highlighted Works

Bibb Balancing: Regulatory Mismatches Under the Dormant Commerce Clause (with Michael S. Knoll), 91 George Washington Law Review 1 (2023).

Solidarity Federalism (with Erin F. Delaney), 98 Notre Dame Law Review 618–670 (2023).

The Transformation of International Tax, 114 American Journal of International Law 353-402 (2020).

Identifying Illegal Subsidies, 69 American University Law Review 479-564 (2019).

The Economic Foundation of the Dormant Commerce Clause (with Michael S. Knoll), 103 Virginia Law Review 309-354 (2017).

Citizenship Taxation, 89 Southern California Law Review 169-239 (2016).

Delegating Up: State Conformity with the Federal Tax Base, 62 Duke Law Journal 1267-1348 (2013).

What is Tax Discrimination? (with Michael S. Knoll), 121 Yale Law Journal 1014-1117 (2012).

Federalism and the Taxing Power, 99 California Law Review 975-1036 (2011).

Tax Expenditures and Global Labor Mobility, 84 NYU Law Review 1540-1622 (2009).

Made in America for European Tax: The Internal Consistency Test, 49 Boston College Law Review 1277-1326 (2008).

Flunking the ECJ's Tax Discrimination Test, 46 Columbia Journal of Transnational Law 72-132 (2007).

U.S. Tax Treaty Policy and the European Court of Justice, 59 Tax Law Review 65-132 (2005).

Complete List of Works

Forthcoming

Bounded Extraterritoriality (with Michael S. Knoll), Michigan Law Review (2023).
Does the Prohibition of State Aid Limit Tax Competition?, Oxford Yearbook of European Law (2023).

Books

Thinker, Teacher, Traveler: Reimagining International Tax (edited with Georg Kofler & Alexander Rust), IBFD (2021).
Primer on Direct Taxation in the European Union, Thomson/West (2005).

Book Chapters

Tax Discrimination (with Elizabeth Adams & Michael Knoll), in Research Handbook on International Taxation, Edward Elgar, 44–63 (2020).

Articles & Reviews

Bibb Balancing: Regulatory Mismatches Under the Dormant Commerce Clause (with Michael S. Knoll), 91 George Washington Law Review 1 (2023).
Solidarity Federalism (with Erin F. Delaney), 98 Notre Dame Law Review 618–670 (2023).
Ding-Dong! The EU Arm’s-Length Standard Is Dead, 108 Tax Notes International 1249 (2022).
National Pork is a Bibb Case, Not a Pike Case (with Michael S. Knoll), 91 George Washington Law Review Arguendo 1–13 (2022).
A Wrench in the GLOBE's Diabolical Machinery, 107 Tax Notes International 1391 (2022).
Has Cross-Border Arbitrage Met Its Match? (with Pascal Saint-Amans), 41 Virginia Tax Review (2021).
The 2021 Compromise, 172 Tax Notes Federal 569 (2021).
Special Report on EU State Aid: Part 9—State Aid Enforcement After Amazon, 171 Tax Notes Federal 1395–1402 (2021).
Special Report on EU State Aid: Part 8—State Aid: The General Court Decision in Apple (with Stephen Daly), 168 Tax Notes Federal 1791–1806 (2020).
Steiner v. Utah: Designing a Constitutional Remedy (with Michael S. Knoll), 95 Tax Notes State 845–850 (2020).
The Dormant Foreign Commerce Clause After Wynne (with Michael S. Knoll), 39 Virginia Tax Review 357–418 (2020).
The Legality of Digital Taxes in Europe (with Leopoldo Parada), 40 Virginia Tax Review 175–217 (2020).
The Transformation of International Tax, 114 American Journal of International Law 353–402 (2020).
Why the Supreme Court Should Grant Certiorari in Steiner v. Utah (with Michael S. Knoll), 95 Tax Notes State 377–388 (2020).
Special Report on EU State Aid: Part 7—Implications of the Rulings in Starbucks And Fiat for the Apple State Aid Case, 154 Tax Notes Federal 93–100 (2019).
Company Size Matters (with Leopoldo Parada), 2019 British Tax Review 610–650 (2019).
Identifying Illegal Subsidies, 69 American University Law Review 479–564 (2019).
Digital Battlefront in the Tax Wars (with Leopoldo Parada), 92 Tax Notes International 1183–1197 (2018).
Dual Residents: A Sur-Reply to Zelinsky, 158 Tax Notes 269–272 (2018).
Implications of Wayfair, 46 Intertax 810–819 (2018).
Special Report on EU State Aid: Part 6—Arm's Length on Appeal, 158 Tax Notes 771–796 (2018).
New York’s Unconstitutional Tax Residence Rule (with Michael S. Knoll), 85 State Tax Notes 707–716 (2017).
Special Report on EU State Aid: Part 1—FAQ, 154 Tax Notes 451–462 (2017).
Special Report on EU State Aid: Part 2—Legitimate Expectations, 154 Tax Notes 615–622 (2017).
Special Report on EU State Aid: Part 3—Apple, 154 Tax Notes 735–751 (2017).
Special Report on EU State Aid: Part 4—Whose Arm's-Length Standard?, 155 Tax Notes 947–966 (2017).
Special Report on EU State Aid: Part 5—An American View of State Aid, 157 Tax Notes 645–662 (2017).
The Economic Foundation of the Dormant Commerce Clause (with Michael S. Knoll), 103 Virginia Law Review 309–354 (2017).
Citizenship Taxation, 89 Southern California Law Review 169–239 (2016).
Is the Philadelphia Wage Tax Unconstitutional? And If It Is, What Can and Should the City Do?, 164 University of Pennsylvania Law Review Online 163–178 (2016).
Comptroller v. Wynne: Internal Consistency, a National Marketplace, and Limits on State Sovereignty to Tax (with Michael S. Knoll), 163 University of Pennsylvania Law Review Online 267–283 (2015).
How the Massachusetts Supreme Judicial Court Should Apply Wynne (with Michael S. Knoll), 78 State Tax Notes 921–928 (2015).
Wynne: It’s Not About Double Taxation (with Michael S. Knoll), 75 State Tax Notes 413–422 (2015).
Exporting FATCA (with Joshua D. Blank), 142 Tax Notes 1245–1250 (2014).
Waiting for Perseus: A Sur-Reply to Professors Graetz and Warren (with Michael S. Knoll), 67 Tax Law Review 375–452 (2014).
Delegating Up: State Conformity with the Federal Tax Base, 62 Duke Law Journal 1267–1348 (2013).
What is Tax Discrimination? (with Michael S. Knoll), 121 Yale Law Journal 1014–1117 (2012).
The Constitutional Limits of Taxing and Spending, 38 Administive & Regulatory Law News 2–3, 12 (2012).
Federalism and the Taxing Power, 99 California Law Review 975–1036 (2011).
Tax Discrimination and Capital Neutrality, 2 World Tax Journal 126 (2010).
Tax Expenditures and Global Labor Mobility, 84 NYU Law Review 1540–1622 (2009).
Made in America for European Tax: The Internal Consistency Test, 49 Boston College Law Review 1277–1326 (2008).
Sovereign Wealth Funds and the Efficient Management of the Wealth of Nations, 120 Tax Notes 1321 (2008).
Constitutional Restraints on Corporate Tax Integration (with Walter Hellerstein & Georg W. Kofler), 62 Tax Law Review 1–66 (2008).
Double Taxation: A European "Switch in Time"? (with Georg W. Kofler), 14 Columbia Journal of European Law 63–98 (2007).
Flunking the ECJ's Tax Discrimination Test, 46 Columbia Journal of Transnational Law 72–132 (2007).
Common Markets, Common Tax Problems, 8 Florida Tax Review 599–628 (2007).
When Tax Treaty Derivative Benefits Provisions Don’t Apply, 43 Tax Notes International 563–567 (2006).
U.S. Tax Treaty Policy and the European Court of Justice, 59 Tax Law Review 65–132 (2005).

Reports & Datasets

Brief of Professors Michael Knoll and Ruth Mason as Amici Curiae Supporting Petitioners in National Pork Producers Council v. Ross (with Michael Knoll) (2022).
U.S. Supreme Court Amici Curiae Brief in Support of Petitioner, South Dakota v. Wayfair, Inc. (with Alex Brill, Michael Knoll & Alan D. Viard)138 , S. Ct. 2080 (2018).
Brief of Amici Curiae On Remand From The United States Supreme Court First Marblehead, Inc., v. Comm’r (with Michael S. Knoll)470 , Mass. 497 (2016).
Brief of Michael S. Knoll and Ruth Mason as Amici Curiae in Support of Respondents, Comptroller of Treasury of Maryland v. Wynne (with Michael S. Knoll)575 , U.S. 542 (2015).

Op-Eds, Blogs, Shorter Works

Is it Kosher for California to Ban Out-of-State Pork? (with Michael S. Knoll), The Regulatory Review (December 5, 2022).
Is the Biggest Supreme Court Case This Term About Bacon? (with Michael S. Knoll), The Regulatory Review (November 14, 2022).
The Fine Print on the Global Tax Deal: Domestic Politics Could Prevent Sweeping Reform, Foreign Affairs (November 8, 2021).
Apple Just Saved $14 Billion in Tax — But Can the Tax System Be Saved?, The Hill (July 19, 2020).
The Time Has Come for State Digital Taxes (with Darien Shanske), Daily Tax Report (May 29, 2020).
Will Coronavirus Accelerate Digital Tax Adoption?, Brink News (May 10, 2020).
What the States Need from Congress Now Is Cold, Hard Cash (with Daniel Hemel & Gladriel Shobe), Time (April 14, 2020).
France-US skirmish over Amazon digital tax shows why the century-old international tax system is broken, The Conversation (January 31, 2020).
Maryland’s Proposed Digital Tax May Be Unconstitutional, Medium (January 30, 2020).

IN THE NEWS

12/05/2022
Is It Kosher for California To Ban Out-of-State Pork? (The Regulatory Review)
11/14/2022
Is the Biggest Supreme Court Case This Term About Bacon? (The Regulatory Review)
10/18/2022
Md. Digital Ad Tax Quash Likely To Chill Other State Proposals (Law360)
10/14/2022
Calif. Pork Law Fight May Guide Post-Wayfair Tax Challenges (Law360)
10/13/2022
Can Gorsuch Rally Court Against Dormant Commerce Clause? (Law360)
07/27/2022
US Risks Losing Billions in Taxes as Congress Spurns Global Deal (Bloomberg)
06/17/2022
SCOTUS Oral Arguments Set on Prop 12 (DTN)
05/18/2022
Yellen’s Grand Global Corporate Tax Plan Risks Flop in Congress (Bloomberg News)
05/18/2022
Poland’s Min. Tax Objection Toes Line Between Policy, Politics (Law360)
11/08/2021
The Fine Print on the Global Tax Deal (Foreign Affairs)
10/22/2021
Change in International Tax (Jotwell)
10/08/2021
Over 130 Countries Clinch a Deal That Could Radically Reshape How Companies Are Taxed (NPR)
08/25/2021
Is the OECD/G-20 Tax Agreement the Best Compromise? (Tax Analysts)
06/22/2021
Can We Stop Corporations from Hiding Their Profits Overseas? (The New Yorker)
02/12/2021
Maryland Approves Country’s First Tax on Big Tech’s Ad Revenue (The New York Times)
01/05/2021
US Tariffs On France To Take Effect In Digital Tax War (Law360)
09/14/2020
Luxembourg Tries To Shed ‘Tax Haven’ Label (Financial Times)
08/14/2020
iWin: A Closer Look at Apple’s State Aid Victory (Tax Analysts)
08/10/2020
A Closer Look At Apple’s Victory In EU Tax Case (Forbes)
07/19/2020
Apple Just Saved $14 Billion in Tax — but Can the Tax System Be Saved? (The Hill)
05/29/2020
INSIGHT: The Time Has Come for State Digital Taxes (Bloomberg Tax)
05/10/2020
Will Coronavirus Accelerate Digital Tax Adoption? (Brink News)
04/14/2020
What the States Need From Congress Now Is Cold, Hard Cash (TIME)
03/23/2020
Maryland Lawmakers Approve New Digital Tax, Which Critics Contend Will Undermine U.S. Pushback Against Foreign Digital Tax Efforts (Forbes)
03/08/2020
How the Rich Stay Rich: Behind the Velvet Curtain (Global Inquirer)
02/24/2020
High Court Won’t Review Utah Tax Credit Case (Law360)
01/31/2020
France-US Skirmish Over Amazon Digital Tax Shows Why the Century-Old International Tax System Is Broken (The Conversation)
01/30/2020
Maryland’s Proposed Digital Tax May Be Unconstitutional (Medium)
01/24/2020
The Power of Semantics (Politico)
01/17/2020
Digital Tax Bill in Maryland Could Face Legal Hurdles (Bloomberg Tax)
01/17/2020
Digital Tax Hits Close to Home (Politico)
12/31/2019
Top 100 Must-Follow Tax Twitter Accounts For 2020 (Forbes)
12/10/2019
Will A Wealth Tax Work in the U.S.? | Ruth Mason (WINA Radio)
07/29/2019
Sen. Warren Vows To Comply With OECD Trade, Treaty Rules (Law360)
07/22/2019
Altera Asks Ninth Circuit to Revisit Landmark Tax Case (Bloomberg Tax)
06/26/2019
Ruth Mason on Tax Liabilities Abroad (Knowledge@Wharton)
05/02/2019
Digitalization and Taxation: the New International Legal Order (University of Turin)
02/05/2019
National Digital Taxes Could Face State Aid Challenge In EU (Law360)
02/04/2019
‘A Very Big Experiment:’ How Elizabeth Warren Would Try Forcing Billionaires To Pay Her Wealth Tax (The Washington Post)
11/27/2018
From “BEPS Inaction 1” to “BEPS 2.0” (Medium)
11/14/2018
Unfriending European Tech Taxes (The Hill)
10/08/2018
A U.S. View of State Aid (Institute for Business Development)
04/11/2018
SCOTUS Should Balance Main Street and Online (Real Clear Markets)
03/12/2018
Digital Nexus in the EU and United States (Tax Notes International)
02/28/2018
UH Law Center Spring 2018 Distinguished Speaker Series: Virginia School of Law Professor Ruth Mason Examines Changing EU Tax Policy (University of Houston Law Center)
01/29/2018
High Court Should Lift Tax Ban on Export Purchases: Professors (Bloomberg BNA)
05/04/2016
Should Phila. Let its Illegal Wage Tax Die? (The Philadelphia Inquirer)
12/14/2015
U.S. Supreme Court Decision Imperils a Portion of Wage tax in Philadelphia and Wilmington (Plan Philly)
10/14/2015
Conference Focuses on Intersection of Tax Law and Citizenship (Michigan Law)
05/26/2015
Amazon Buckles to EU Pressure -- Will Google, Apple, Others Follow Suit? (The Street)
05/18/2015
Taxpayers Backed by U.S. High Court on Out-of-State Income (Bloomberg)
09/24/2014
American Expats Renounce Citizenship After Banking Laws Make Life Hard (The Guardian)
09/18/2014
S&P 100 Tax Rate Report (WalletHub)
06/25/2014
FATCA Will Help Catch Tax Cheats, Not Lead to the Dollar’s Collapse (Fortune)
09/13/2013
Same-Sex Married Couples See New State-Law Tax Complexity (Bloomberg)

AT UVA LAW

Constitutional Comparisons on Commerce
New Directors Lead Academic Centers, Programs
Feminism Confronts Homo Economicus: Gender, Law, and Society
Testing Theories of American Politics
Accolades: UVA Law No. 2 in Alumni at Top Firms
Political Fragmentation in Democracies Today
Professor Predicts Big Tech Pushback May Dampen New Global Tax Strategy
Professors Elected to American Law Institute
The Transformation of International Tax
Building a Law-and-Political-Economy Framework: Beyond the Twentieth-Century Synthesis
Value Creation by Business Lawyers
Understanding the ‘Code of Capital’
UVA Notches Third Straight International Tax Law Moot Court Championship
Tax Scholars Join Coalition Finding Solutions to Pandemic-Induced State Financial Crises
Professor Outlines Challenges Facing Wealth Tax Proposals
UVA Repeats as International Tax Law Moot Court Champions
‘Common Law’ Explores Taxing Big Tech, Evolution in International Tax
‘Common Law’ Episode 3: Taxing Big Tech and the Future of International Tax
The Future of Law
Why the Supreme Court Leveled the Playing Field on E-Commerce
Michael Knoll, Ruth Mason and Charlie Trost on South Dakota v. Wayfair
UVA Becomes First U.S. Team To Take All at International Tax Law Moot Court
Ruth Mason Will Be Professor in Residence at Tax Institution in Amsterdam
Law Students Take Home Multiple Awards in International Tax Law Moot
Tax Stars
3L Amanda Leon's International Tax Law Paper Wins Major Writing Competition
Professor A. Benjamin Spencer Named Author of Massively Cited 'Federal Practice and Procedure'
Mason Named National Reporter at Congress of European Association of Tax Law Professors
International Tax Expert Ruth Mason to Join UVA Law Faculty
Constitutional Comparisons on Commerce

Featured Scholarship