June 2, 2015 4:45PM # Senate Hearing on *King v. Burwell* This Thursday By [Michael F. Cannon](https://www.cato.org/people/michael-f-cannon) --- SHARE At 2pm this Thursday, I will be testifying before the Senate Judiciary Committee’s Subcommittee on Oversight, Agency Action, Federal Rights and Federal Courts at a [hearing](http://www.judiciary.senate.gov/meetings/rewriting-the-law-examining-the-process-that-led-to-the-obamacare-subsidy-rule) investigating how the Internal Revenue Service developed the ([illegal](https://object.cato.org/sites/cato.org/files/articles/cannon-adler-health-matrix-23.pdf)) “tax-credit rule” challenged in *King v. Burwell*. Witnesses include three Treasury and IRS officials involved in drafting the rule: Panel I The Honorable Mark Mazur Assistant Secretary for Tax Policy Department of the Treasury (invited) Ms. Emily McMahon Deputy Assistant Secretary for Tax Policy Department of the Treasury (invited) Ms. Cameron Arterton Deputy Tax Legislative Counsel for Tax Policy Department of the Treasury (invited) The second panel will consist of **Michael Carvin** (lead attorney for the plaintiffs in *King v. Burwell*, who [argued](https://cei.org/sites/default/files/KING%20v%20BURWELL%20-%20No.%2014-114%20-%20Petitioners%20Opening%20Brief%20of%20the%20Merits%20-%20December%2022%202014.pdf) the case before the Supreme Court), University of Iowa tax-law professor **Andy Grewal** (who [discovered three additional ways](http://www.yalejreg.com/blog/more-unlawful-aca-premium-tax-credits-by-andy-grewal), beyond *King*, that the IRS expanded eligibility for tax credits beyond clear limits imposed by the ACA), and me. ##### Related Tags [Government and Politics](https://www.cato.org/government-politics), [Health Care](https://www.cato.org/health-care), [Constitutional Law](https://www.cato.org/constitutional-law), [Robert A. Levy Center for Constitutional Studies](https://www.cato.org/robert-levy-center-constitutional-studies) [![Creative Commons License](/build/cato_2020/images/creative-commons.svg)](http://creativecommons.org/licenses/by-nc-sa/4.0/) This work is licensed under a [Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License](https://creativecommons.org/licenses/by-nc-sa/4.0/).