There has been lots of speculation about just what — if anything — Justice Roberts, Sotomayor and the rest of the U.S. Supreme Court will do about the federal Affordable Care Act.

Could they strike down just part of the law? Two constitutional law scholars offer their take.

Suppose, just suppose, the U.S. Supreme Court decides that the individual mandate is bad law.

Remember, that's the rule that requires most Americans to purchase health insurance or pay a penalty. The argument goes: When too few people have health coverage, care costs and insurance prices are unacceptably high for everyone else and that causes reverberations throughout the economy.

"The claim by people who object to this law, is that the power to regulate commerce is not the power to command somebody to do commerce, said Widener School of Law professor Michael Dimino. "The government can't tell me I need to buy a car, it's up to me."

Mandate supporters argue that the government's authority is more expansive than that.

"Pretty much that Congress has the power to pass whatever laws it wants as long as Congress feels those law are necessary to have certain economic effects," Diminio said.

So, if the court strikes down the individual mandate, what then? Lawyers call it a question of "severance." If the court cuts away one part of the health law, does the rest crumble? To get to an answer, Dimino says the justices have to try to suss out Congress' intentions -- travel back in time and put themselves in the minds of the lawmakers.

"It's basically impossible to figure out with any level of certainty, but that's what the court goes through," Dimino said.

Sometimes it's easy.

"If you have a really minor, tangential part of a huge law, you can say all right, we pretty much know that was inessential to the deal, maybe it mattered to a couple of congressman here and there," said Dimino.  He says past high court rulings hint that the mandate is severable.

"The court typically places a big thumb on the scale in favor of severability," said Seton Hall law professor John Jacobi. "They don't want to strike down more laws than they need to."

"I just don't think that modern Supreme Court precedent supports the Supreme Court getting that involved in the business of the legislature," Jacobi said.

The health law is wide ranging with expansion plans for Medicaid, new rules for insurance companies, changes in Medicare, as well as steps to prevent fraud and abuse.

The justices will scour the language in the law and study the political tradeoffs brokered during the health care debate to try to figure out if Congress considered the mandate essential.

"Did it intend that the entire statue would go forward if this little piece were stricken, or did they intend that it would fall?" Jacobi asked.

He sees at least three possibilities. One: Call the mandate unconstitutional; kill the entire law. Two: kill the mandate; let everything else stand.

Jacobi expects the government to offer a third option.

"The Obama administration says: 'Please don't strike the individual mandate, but if you do, please also strike two additional provisions,'" he said.

The solicitor general may argue that without the individual mandate, two particular reforms won't work.

"Guarantee issue" is the rule coming in 2014, that forces companies to sell coverage to anyone who walks through the door. "Community rating" forbids firms from considering a person's past health status when they set premium prices — rates are based on where you live, age et cetera, but not individual health history.

Crafters got insurance companies on board with "guarantee issue" and "community rating" based on the premise that the individual mandate would bring more people into the system. They say those changes would be too expensive if healthy young people are not forced to buy health insurance.

One last reminder from the constitutional scholars. The Supreme Court is not deciding whether they like the health law or not, but rather whether Congress had the power to make the decisions it made-wise or not.