摘要:In King v. Burwell, the Supreme Court did not rely on Chevron to hold valid tax regulations allowing tax credits for taxpayers who enroll in an insurance plan through a federal rather than a state exchange. It instead concluded, relying in good measure on Brown and Williamson, that Congress had not delegated the question at issue to the IRS. It thus introduced a so-called Chevron Step 0. This essay reviews the Tax Court’s use of Chevron and Brown & Williamson to conclude that the Tax Court may well make use of King v. Burwell to review and reject tax regulations under this Chevron Step 0.