Judge Reed C. O’Connor should certify his ruling invalidating the Affordable Care Act for immediate appeal, the parties to the case agreed.

An order allowing the U.S. Court of Appeals for the Fifth Circuit to review O’Connor’s legal conclusions sooner rather than later would be “prudent,” 16 blue states and the District of Columbia told the U.S. District Court for the Northern District of Texas Dec. 26.

The judge’s Dec. 14 order wasn’t final and has no immediate effect, the states’ brief said. A prompt appeal is needed “to avoid the widespread confusion and extraordinary disruption that would” occur if the litigation followed its normal course, they said.

The federal government registered its support for an order certifying the case for an interlocutory appeal Dec. 21.

O’Connor said the individual mandate, which requires everyone to have health insurance, couldn’t survive a constitutional challenge after Congress repealed a “tax” imposed for noncompliance in 2017. The provision couldn’t be removed, or “severed,” to save the rest of the ACA, he added.

Whether the individual mandate is severable is a “controlling question of law as to which there is substantial ground for difference of opinion” that should be determined by the appeals court, the government said in a brief responding to the blue states’ Dec. 17 motion to clarify the decision.

The plaintiff red states also agreed Dec. 21 that O’Connor should certify the decision for an immediate appeal. That would be the “natural” next step in the litigation, they said.

The case is Texas v. United States, N.D. Tex., No. 18-cv-167, reply brief filed 12/26/18.