Though Thursday morning’s Supreme Court decision to uphold key parts of the Patient Protection and Affordable Care Act has been seen as complicated and, in some cases, unexpected, several Harvard Law School professors have said that the 5-4 ruling vindicated some of their own predictions and will have significant consequences for future application of key constitutional issues.

In the majority opinion of the court’s long-awaited decision, Chief Justice John G. Roberts ’76 explained that the law’s most contentious provision—the individual mandate that imposes a penalty on those who have not bought health insurance—was constitutional under Congress’s power to tax.

The ruling’s other significant implication has been the limiting of the ACA’s unprecedented expansion of health care for the poor and disabled, ruling that the threat of removal of all federal funds from existing state Medicaid programs to those states that do not comply was unconstitutional.

Several professors indicated that, apart from the potential important political ramifications of the decision in the presidential race between President Barack Obama and former Massachusetts Governor Mitt Romney, the decision will have long-ranging implications in the realm of constitutional law.

For constitutional law professor Laurence H. Tribe ’62, Roberts’ alignment with the court’s more liberal justices on the question of taxation was not as unexpected as many analysts have said.

“Although it’s surprising how few people seem to have noticed, Chief Justice Roberts signaled on the very first day of oral argument this March that he saw this mandate as merely a tax, a view I had also expressed in my Boston Globe editorial on April 3, 2011,” Tribe wrote in an email.

Professor Einer R. Elhauge ’82 noted that the U.S. government had an advantage because of the multiple defenses for the overhaul, including Congress's power to tax. He noted, however, that most of the justices did not discuss the power to tax.

“Most of the justices didn’t express a view on that because they were so concerned with the commerce clause,” Elhauge said.

Yet other scholars were less convinced that the court's decision was a vindication of the federalism that universal healthcare represents.

For professor Richard D. Parker, the decision confirmed his belief that the majority of the court would choose to establish limitations on the power of the commerce clause. Though Roberts ultimately sided with liberal justices Elena Kagan, Sonia Sotomayor, Stephen Breyer, and Ruth Bader Ginsburg, his majority decision made clear that he agreed with the four more conservative justices when it came to the federal government’s power to regulate interstate commerce.

“The sharp, bold break with commerce clause precedent, in the long run, will be what’s most important about the five-four decision,” Parker said.

Constitutional law professor Richard H. Fallon, however, took a different view of the ruling’s implications on the future of Congressional power for economic regulation.

“The individual mandate is sufficiently unusual that I don’t think the fact that the Supreme Court said Congress can’t use it under the commerce clause has any surprising or far-reaching implications,” Fallon said.

Yet Fallon also said that the ruling could restrain federal power, namely because of the limitations set on Medicaid.

“This is the first time in 70 or more years that the Supreme Court has ever said that Congress violated the Constitution by trying to attach strings to federal money in the sense of telling the states that if you take our money you’ve got to do exactly what we’re telling you to do,” Fallon said.

Most professors expressed some degree of admiration for Roberts, whose vote for the health care overhaul was seen as crucial.

“It’s enormously gratifying that the Chief Justice, whose views count while of course mine don’t, saved the day,” Tribe wrote.

Fallon praised Roberts for stepping out of line with the rest of the conservative justices.

“People don’t like to disappoint their friends, and Roberts’ lifelong friends will be overwhelmingly disappointed in what he did today,” Fallon said on Thursday. “Whatever you think of Roberts as a Chief Justice, what he did was brave and I’m sure he did it because he thought just what the law required. Today, hats off to John Roberts.”