The Catholic order of nuns, the Little Sisters of the Poor, recently scored a historic legal victory, but the outcome left doubt and confusion among observers. Dwight Duncan of the University of Massachusetts School of Law says the opaque ruling appears to have been a deliberate move to “save face” for the federal government. Further, it gave no constitutional resistance to the practice of imposing regulations under the guise of tax penalties.

The scuffle with the federal government came to the fore in 2012, with the Affordable Care Act’s contraceptive mandate in effect. There were already state and federal contraceptive mandates, or at least such interpretations with the 1964 Civil Rights Act and anti-discrimination arguments. However, the latest addition meant that all medical-insurance plans would need contraceptive coverage with no co-pay, and the list included more controversial procedures known as abortifacients. Paying for that was a bridge too far for the devout nuns, and they forged on in spite of lower-court losses.

On May 16, the Supreme Court justices decided to vacate all the lower-court rulings in the case, so the contraceptive mandate would not stand in the face of civil disobedience from the Little Sisters; hence the celebration from the nuns and their Becket Fund legal team. Not without irony, federal officials now have to find another way to get unencumbered contraceptive provisions to the celibate nuns and their colleagues.

Flying under the radar, though, was the less rosy news — in particular, how the ruling would impact other mandates and their imposition on non-religious people. Since Duncan wrote a “friend of the court” amicus brief in support of the Little Sisters and has followed the case closely, he accepted an interview and the challenge of explaining how to interpret the implications of the Supreme Court’s peculiar deflection. In addition to being a law professor, Duncan is a columnist with the Boston Pilot and a long-time advocate for religious liberty.

While Duncan has described the outcome as “an important victory,” he stressed that the Little Sisters’ case — “unfortunately from [his] perspective” — did not rely on arguments of constitutionality: “It would only apply to religious objections … because this case hinges on a federal law called the Religious Freedom Restoration Act.” In other words, it provides no respite for non-religious people, and one could easily characterize the application of the mandate as discriminatory.

There is also the pesky problem of how the mandates of the 2010 Affordable Care Act invoke taxes, strictly speaking, and not fines. In the case of the individual mandate, the Supreme Court ruled that it would be unconstitutional as a regulation, so it only sneaked through as a tax penalty.

Here too there is no let up. Duncan does not “think that [mandates] will be vulnerable to attacks as a tax. [Only] if you object on religious grounds, then you have a pretty solid basis, [including] for-profit, closely held business corporations.”

He further explains that a tax penalty only counts as a regulation when it is “coercive,” and that there is an ill-defined spectrum. Sin taxes on liquor and tobacco do not meet this threshold, since they are so easily avoided. However, that seems to have just been reversed in the case of the Little Sisters, with a tax on not doing something — providing medical coverage with contraceptives. That is why the religious angle was necessary.

This approach of mandating activities by way of tax penalties goes back a long way. In fact, state-administered Unemployment Insurance (UI) programs exist on this very basis, dating back to 1935. The federal government imposes a 6 percent UI tax on incomes, only to refund 90 percent of it if the state has a compliant UI program. How that is not just an outright fine is dubious, but it has worked as far as federal officials wanted submission from the states. All 50 are in line, and no legal challenge has reversed the tactic.

Only recently has there been pushback, but in the extreme case of the federally mandated Medicare expansion at the state level. Duncan explains that states had to extend their Medicare plans to cover a whole new set of beneficiaries and benefits. “If they didn’t do it, then the federal government would take away not just the additional Medicare funds that they would get from the federal government, but all their Medicare funds. And [the Supreme Court said] that provision of the law was unconstitutional, because it was an offer that the states couldn’t refuse. It was coercive. The penalty was so extreme, that it was no longer a tax.”

Duncan acknowledges that this appears to be mental gymnastics, but he says the theory is that the federal government has limited powers: “These distinctions are ways of trying to make that promise or that vision of the Constitution somewhat of a reality.”

“Whenever a tax becomes so onerous that it becomes ‘coercive’ … you still have the argument that it’s an unconstitutional penalty, not a tax. Because then it becomes a form of regulation rather than taxation.”

As far as legal battles go, the challenge then is to lower and better define the coercion threshold, against the use of tax penalties as laws. That way the federal government either has to write the law explicitly or accept greater constitutional restraint and respect for state jurisdiction.

Follow Dwight Duncan on Twitter: @DwightDuncan4.