There are three ways to think about whether a law is constitutional

Randy Barnett observes:

Does it conflict with what the Constitution says? Does it conflict with what the Supreme Court has said? Will five justices accept a particular argument? Although the first three of the potential constitutional challenges to health-care reform have a sound basis in the text of the Constitution, and no Supreme Court precedents clearly bar their success, the smart money says there won't be five votes to thwart the popular will to enact comprehensive health insurance reform.

But what if five justices think the legislation was carried bleeding across the finish line on a party-line vote over widespread bipartisan opposition? What if control of one or both houses of Congress flips parties while lawsuits are pending? Then there might just be five votes against regulating inactivity by compelling citizens to enter into a contract with a private company. This legislation won't go into effect tomorrow. In the interim, it is far more vulnerable than if some citizens had already started to rely upon its benefits.

If this sounds far-fetched, consider another recent case in which the smart money doubted there were five votes to intervene in a politicized controversy involving technical procedures. A case in which five justices may have perceived that long-established rules were being gamed for purely partisan advantage.

You might have heard of it: Bush v. Gore.