The PPACA individual mandate provision calls for many individuals to have health coverage in 2014 or else pay a penalty.

Some have argued that the court must strike all of PPACA if it knocks out any part of the act, because Congress included no "severability clause," or provision declaring that the act as a whole remains valid if part of the act is tossed out.

Kennedy seemed to express frustration with lawyers for both sides as the day went on.

Paul Clement, a lawyer representing the states that have sued to block implementation of PPACA, made the argument that the court should invalidate most or all of the rest of the act if it rejects the individual coverage mandate.

Kennedy asked what test Clement would have the court use to decide when it can kill just part of a law or when it must kill the entire law.

"Is it whether as a rational matter separate parts could still function, or does it focus on the intent of the Congress?" Kennedy asked.

He gave an example of Congress passing an airline bill and a milk bill together, in the same package.

"Then one is declared unconstitutional," Kennedy said. "The other can operate completely independently. Now, we know that Congress would not have intended to pass one without the other. Is that the end of it, or is there some different test? Because we don't want to go into legislative history, that's intrusive, so we ask whether or not an objective — as an objective rational matter one could function without — I still don't know what the test is that we are supposed to apply."

"I'm a big believer in objective tests, Justice Kennedy," Clement said. "I would be perfectly happy with you to apply a more textually based objective approach. I think there are certain justices that are more inclined to take more of a peek at legislative history, and I think if you look at the legislative history of this it would only fortify the conclusion that you would reach from a very objective textual inquiry. But I am happy to focus the court on the objective textual inquiry."

Chief Justice John Roberts said he did not understand Clement's response, and Kennedy asked Clement again to describe an objective test the court could use. Justice Elena Kagan said she was not sure the Supreme Court had ever refused to sever a rejected provision from an act for the reasons Clement was providing.

Justice Stephen Breyer asked why the court should refuse to sever provisions such as a PPACA provision promoting breastfeeding if the court ends up invalidating the individual coverage mandate.

Roberts talked about severability earlier.

Much of the content of PPACA "is reauthorization of appropriations that have been reauthorized for the previous 5 or 10 years, and it was just more convenient for Congress to throw it in in the middle of the 2,700 pages than to do it separately," Roberts said. "I mean, can you really suggest — I mean, they've cited the Black Lung Benefits Act and those have nothing to do with any of the things we are talking about."

Later, however, Kennedy told Edwin Kneedler, a lawyer representing the Obama administration, that severing the individual mandate from the rest of the PPACA could be a more extreme exercise of judicial power than knocking down the whole act.

"We would be exercising the judicial power if one act was — one provision was stricken and the others remained to impose a risk on insurance companies that Congress had never intended," Kennedy said. "By reason of this court, we would have a new regime that Congress did not provide for, did not consider."

Link to the unofficial Supreme Court transcript of the oral arguments.

Link to the Supreme Court MP3 audio recording of the oral arguments.

This story originally appeared on LifeHealthPro, a sister site to PC360.