By Tony Mauro

The U.S. Supreme Court’s liberal wing—the three female justices, plus Stephen Breyer—flexed its muscles again Wednesday during contentious arguments over mandated insurance coverage for contraception under the Affordable Care Act.

The four liberals tried to undercut arguments made by religious nonprofit employers including Little Sisters of the Poor, which operates nursing homes. The plaintiffs assert that the mandate—as well as the workaround the Obama administration adopted to defuse their concern—would force them to enable contraception, contrary to their faith.

When Chief Justice John Roberts Jr. said at one point that women could obtain contraception coverage on exchanges established by the health care law, Justice Sonia Sonia Sotomayor interjected “That’s a falsehood!” an accusation that doesn’t come from a justice’s mouth every day.

Their aggressive questioning echoed the liberals’ similar pummeling of advocates in equally combative arguments in the Texas abortion clinic case Whole Woman’s Health v. Hellerstedt on March 2.

The liberals may be emboldened by the absence in both cases of Justice Antonin Scalia, who usually dominated oral argument without competition. Or, for the female justices at least, it may be another instance of asserting their voices on women’s issues about which men have a “blind spot,” as Justice Ruth Bader Ginsburg once put it.

This time, the liberal justices bolstered their arguments by citing key amicus curiae briefs, which have proliferated in number over recent years, but aren’t always on the tips of the justices’ tongues at argument. A recent study found that Roberts Court justices mention amicus briefs in roughly one-seventh of all oral arguments.

The conservative justices were not shy either on Wednesday, with Roberts accusing the government of “hijacking” the insurance plans of religious employers, and Samuel Alito Jr. questioning why it would be a burden for female employees to find contraceptive coverage on their own separately. Alito also cited an amicus brief to drive home his arguments against the mandate.

A brief look at the briefs that figured prominently in the argument Wednesday:

Laycock switches sides: A brief by University of Virginia School of Law professor Douglas Laycock earned five mentions on Wednesday, with Ginsburg describing him as “our leading proponent of RFRA,” the Religious Freedom Restoration Act. That is the law that religious employers have invoked in resisting the contraceptive mandate, but in this case Laycock wrote that religious objectors are asking too much from the law—a counterintuitive stance that may explain why his brief for the Baptist Joint Committee for Religious Liberty got so much attention.

Noting that the religious-employer plaintiffs are seeking the same exemption from contraceptive coverage that the law already gives more narrowly to churches and religious orders, Laycock said such an expansion would have the effect of discouraging legislators from making any exceptions for religious objectors. He called the plaintiff’s request “a mortal threat to thousands of specific religious exemptions crafted by legislatures and administrative agencies. Specific religious exemptions necessarily have boundaries, and if legislatures and agencies cannot define those boundaries, specific exemptions will not be enacted at all.”

Justice Elena Kagan cited Laycock’s brief first, to make the point that “there are people who are extremely strong RFTA supporters who have deserted this cause.”

Paul Clement of Bancroft, who represented some of the plaintiffs, told the court Wednesday that since writing the brief, Laycock has “admitted he didn’t understand the particulars of this particular plan.”

In an email, Laycock said it was “absurd” to say that he had retracted his argument. “Amicus briefs get very intermittent reinforcement. You rarely know whether they’re read, but sometimes, you get a signal.”

Military history: The connection between requirements of the Affordable Care Act and military history may seem tenuous, but a brief on behalf of military historians was the first brief mentioned Wednesday.

Sotomayor cited it to draw the analogy between the religious plaintiffs in the case before the court and conscientious objectors throughout U.S. history. Even at the time of the founding and during discussions of the Bill of Rights, the brief states, such objectors were required to pay for someone else to replace them in military service.

David Gans of the Constitutional Accountability Center, who was co-author of the brief, said it advanced “an extremely important point about how religious accommodations have been made through history.”

The Neuborne brief: Breyer invoked the “Neuborne brief” twice on Wednesday, a reference to New York University School of Law professor Burt Neuborne. On behalf of himself and three other former American Civil Liberties Union officials, Neuborne listed Supreme Court cases in which government was allowed to accommodate religious practices by exempting them from various laws, and others when it was not permitted.

“I’m trying to find the basis for the distinction between those things that we do require people to do despite their religious objection, and those things that we don’t,” Breyer said. Neuborne said the distinction between the two groups turns on whether a religious-based exemption would impose costs on third parties.

Blasts from the past: Two religious groups that brought landmark cases before the Supreme Court more than 20 years ago joined in a brief that caught the attention of Alito in arguing against the government’s position.

The Church of the Lukumi Babalu Aye and the International Society for Krishna Consciousness joined with other religious groups in a brief by Aaron Streett of Baker Botts asserting that that “adherents of minority religious would have the most to lose” if the Little Sisters of the Poor and other plaintiffs lose. Alito said, “A great array of religious groups … have said this presents an unprecedented threat to religious liberty in this country.”

Streett said Wednesday: “Allowing the government to irrationally pick and choose which religious groups to exempt from a governmental requirement will often result in discrimination against unfamiliar religions.”