In King v. Burwell, the Supreme Court held that the Patient Protection and Affordable Care Act (ACA) should be read to authorize tax credits for the purchase of health insurance in exchanges established by the federal government lest the ACA’s other reforms destabilize the individual health insurance market in states served by federal exchanges. In “King v. Burwell and the Triumph of Selective Constitutionalism,” Michael Cannon and I dissect the court’s reasoning in King, highlighting the court’s abandonment of textualist principles (as others have noted) and the court’s reliance on a highly selective use of context to support its ultimate conclusion.