A cartoon by Thomas Nast depicting Catholic bishops as crocodiles eager to gobble up American schoolchildren. It first appeared in Harper's Weekly on September 30, 1871.Corbis / Getty

Later this month, the U.S. Supreme Court will hear one of the most significant education cases in decades: Espinoza v. Montana Department of Revenue. Centering around a modest tax-credit scholarship program in Montana, Espinoza could have major ramifications for educational-choice programs across America, which help nearly half a million students attend private schools.

In deciding Espinoza, the Court has the opportunity to do more than just settle the fate of one controversial tax credit; it could also junk Montana’s Blaine Amendment, finding it in violation of the Constitution’s religious-freedom and equal-protection clauses. In doing so, it would set a strong precedent against any law born of bigotry, even if other justifications seem neutral.

The Espinoza case dates back to 2015, when, shortly after state lawmakers enacted the tax-credit scholarship program, the Montana Department of Revenue devised a rule that banned families from using the scholarships to attend religious schools, which account for more than two-thirds of the state’s private schools. The case is brought by three Montana moms whose children are thriving at a private religious school; without the tax-credit scholarships, the families are struggling to pay tuition. (Litigating on behalf of the parents is the Institute for Justice, where I work, though I’m not directly involved with the lawsuit.)

In May 2017, a trial court ruled in their favor and struck down the Department of Revenue’s rule. But in December 2018, the Montana Supreme Court reversed the decision, citing what is commonly known as Montana’s Blaine Amendment. Enacted during a wave of anti-Catholic bigotry in 1889, the amendment bans “direct or indirect” public funding for any “sectarian purpose.” According to the majority opinion, the tax-credit scholarship program violates the Blaine Amendment, even though it’s funded entirely through voluntary, charitable, private donations incentivized by the state’s tax credit. This past summer, the U.S. Supreme Court agreed to hear the case, and it will be argued on January 22.

Today, 37 states have Blaine Amendments in their state constitution, though the precise wording varies. The amendments are named after Representative James G. Blaine of Maine, who in 1876 proposed a federal constitutional amendment that would have prohibited state funding for schools “under the control of any religious sect.” Blaine’s amendment passed the U.S. House of Representatives but fell just short of the supermajority it needed to pass the U.S. Senate.

Even though Blaine’s amendment was never enacted nationwide, Congress later required many potential states to adopt a version of the amendment in order to be admitted to the union. Starting with the Enabling Act of 1889, Congress granted statehood to Montana, North Dakota, South Dakota, and Washington only after their state constitutions guaranteed that their public schools would be “free from sectarian control.” Senator Henry Blair of New Hampshire, who regularly reintroduced the Blaine Amendment in subsequent sessions, called this provision of the Enabling Act “the very essence” of his proposal, and praised Congress for setting a “great precedent.”

At first glance, Blaine Amendments may seem like a benign way to ensure the government’s neutrality toward religion. In the 1875 speech that inspired Representative Blaine, President Ulysses S. Grant called for a federal ban on government funding for “sectarian schools” in order to “keep the Church and state forever separate.” More recently, nine states with Blaine Amendments collectively filed an amicus brief in the Espinoza case, arguing that no-aid provisions like theirs and Montana’s merely “sought to solidify the Framers’ original design separating church and State.”

But Blaine Amendments weren’t truly devoted to the separation of Church and state. Instead, they were mainly focused on separating the Catholic Church and state. Although public schools are largely secular today, that wasn’t the case in the 19th century. Public or “common” schools typically instilled in their students a nondenominational form of Protestantism, requiring them to sing hymns, pray, and read from the King James Bible—in direct conflict with Catholic dogma.

Refusing to send their children to schools that clashed with their values, many Catholic families (often immigrants) created their own private, religiously affiliated school systems. In turn, those parochial schools quickly became a target for bigoted attacks, most infamously by the Know Nothing party, and later by the American Protective Association. The association was particularly powerful in Montana: At the APA’s peak, up to one-tenth of Montana residents were members. The fact that Blaine Amendments featured so prominently in the platforms of those groups clearly shows that prejudice was a motivating factor behind state Blaine Amendments.

The language in Blaine Amendments is another giveaway, given that they targeted “sectarian” schools. As the libertarian think tank Independence Institute detailed in an amicus brief for the Espinoza case, sectarian and religious were not synonymous. Throughout the 19th century, dictionaries and newspapers regularly distinguished the two terms, with sectarian usually considered “a pejorative term for religions viewed negatively.” Nor was sectarian limited to tarnishing Catholics. Essentially, any non-Protestant religious minority could be (and often was) labeled “sectarian,” including Mormons, Jews, and “Mohammedans” (i.e., Muslims).

This distinction was well known to Montana legislators. Prior to statehood, in 1872, Montana passed a law that barred government funding to any public school or school library that distributed “sectarian” books, but it didn’t prevent some public schools from forcing their students to read the King James Bible. Notably, lawmakers had previously tried—and failed—to ban “any publication of a religious character” from the territory’s common schools. Unlike the earlier proposal, which would have been uniformly secular, the 1872 law reinforced a two-tier system that continued to favor Protestants under the guise of battling “sectarianism.”

Further revealing that Blaine Amendments weren’t driven by lofty notions of separating Church and state was the scorn that proponents levied against nonbelievers. For instance, in his 1875 speech, President Grant envisioned providing “every child growing up in the land [with] the opportunity of a good common-school education, unmixed with sectarian, pagan, or atheistical dogmas.”

In 1972, the state’s bitter history became a flash point when its Blaine Amendment was up for re-ratification at a new Montana Constitutional Convention. During the convention, several delegates slammed the state’s Blaine Amendment as a “badge of bigotry” and “remnant … of a long-past era of prejudice.”

Despite those objections, Montana’s Blaine Amendment was re-ratified. The only major difference between the 1889 and 1972 amendments is that under the latter, federal funding for private schools is exempt from Montana’s ban on aid to sectarian schools. And while Montana in 1972 had certainly grown more tolerant toward Catholics since 1889, the new Blaine Amendment was “intended” to “retain the meaning” of its predecessor, as the transcript of the constitutional convention shows and, later, the Montana Supreme Court confirmed.

The U.S. Supreme Court has ruled that prejudiced origins can be reason to invalidate laws decades later. In its 1985 decision Hunter v. Underwood, the Court unanimously struck down a section of the Alabama Constitution that denied the right to vote to people convicted of crimes of “moral turpitude.” Dating back to 1901, the provision was explicitly designed to target African Americans and exclude them from voting. Because racial discrimination was a “substantial or motivating factor” behind disenfranchisement, the Court ruled that it ran afoul of the equal-protection clause.

With its Hunter decision, the Court firmly rejected Alabama’s arguments that the disenfranchisement section was constitutional because it also “discriminate[d] against poor whites” and that “events occurring in the succeeding 80 years had legitimated the provision.”

“Without deciding whether [the Alabama provision] would be valid if enacted today without any impermissible motivation,” Justice William Rehnquist wrote for the Court, “we simply observe that its original enactment was motivated by a desire to discriminate against blacks on account of race, and the section continues to this day to have that effect.”

Although Alabama’s suppression of black liberty was far more egregious than what non-Protestants faced in Montana, there are parallels. Prejudice was a “motivating factor” behind Montana’s Blaine Amendment, which continues to discriminate against private, “sectarian” schools, rather like how the Alabama provision was driven by bigotry and continued to discriminate until it was struck down. In keeping with Hunter, the U.S. Supreme Court similarly should decide that the presence of other motivations and the passage of time aren’t enough to salvage the Blaine Amendment.

In fact, one state’s supreme court has already declared that its state’s Blaine Amendment has been “tainted” by “anti-Catholic sentiment,” even though it seems “religiously neutral.” The day after the Montana Supreme Court’s ruling in Espinoza, the New Mexico Supreme Court upheld a state program that loaned textbooks to private-school students, reversing a decision it had made just three years prior.

Like Montana, New Mexico was required to adopt a Blaine Amendment for statehood and was “caught up in the nationwide movement to eliminate Catholic influence from the school system,” Justice Barbara Vigil recounted. New Mexico’s no-aid provision was even broader, barring state funds not only to sectarian schools but to all private schools as well.

But in light of recent religious-liberty cases, in 2017 the U.S. Supreme Court vacated the 2015 textbook-lending decision. As a result, the New Mexico Supreme Court felt obliged to view the case “through a different lens, one that focuses on discriminatory intent.” “Even though it appears that the people of New Mexico intended for Article XII, Section 3 to be a religiously neutral provision,” Justice Vigil wrote for the court, “the history of the federal Blaine amendment and the New Mexico Enabling Act lead us to conclude that anti-Catholic sentiment tainted its adoption.”

The court now argued that using the state’s Blaine Amendment to invalidate laws could run afoul of the free-exercise clause. In short, thanks to its disreputable origins, the amendment was no longer legitimate. Rather than striking it down, the New Mexico Supreme Court decided to narrowly interpret the amendment instead. To avoid raising any federal constitutional concerns, the court upheld the textbook-lending program, arguing that it “provides a public benefit to students,” while “any benefit to private schools is purely incidental and does not constitute ‘support’ within the meaning” of New Mexico’s Blaine Amendment.

For decades, the U.S. Supreme Court has repeatedly struck down laws and policies that hide their prejudice behind a fig leaf of neutrality. With Espinoza, the high court should seize the opportunity to continue this legacy.

This story is part of the project “The Battle for the Constitution,” in partnership with the National Constitution Center.

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