A central provision of the Affordable Care Act that provides tax breaks for poor people who buy health insurance through federal exchanges could be in jeopardy after heated oral arguments before a three-judge panel on Tuesday at the U.S. Court of Appeals for the D.C. Circuit.

“If legislation is stupid, I don’t see that it’s up to the court to save it,” said Senior Judge A. Raymond Randolph, who described the federal health care law as “cobbled together and badly written.”