A group of Mormon scholars has filed a brief before the U.S. Supreme Court, joining in the wider challenge to the Trump administration’s proposed ban on travelers from six Muslim-majority nations.

Signed by 21 LDS historians, the brief filed Thursday harks back to government crackdowns on Mormon immigration in the 19th century and asks the high court for a stringent review of what critics perceive as religion-based discrimination.

The Trump administration, noting that the targeted nations are unstable or failed states with histories of Islamic extremism, insists it wants a temporary ban on travel from those countries only to allow time to more closely vet arrivals for possible terrorist links.

The brief is written by Nathan B. Oman, an LDS law professor at William & Mary, and Anna-Rose Mathieson of the California Appellate Law Group. It is similar to one filed four months ago before the 9th U.S. Circuit Court of Appeals attacking the ban.

Both briefs urge justices to “take a hard look” at the language of Trump’s proposed order and whether it crosses the line from legitimate presidential action to protect U.S. security to a “Muslim ban,” which could be unconstitutionally discriminatory.

The Supreme Court brief recalled 19th-century U.S. governmental policies seeking to halt immigration of Mormon converts from overseas to America or, failing in that, to turn them away at U.S. ports of entry.

In the 19th century, Mormons and their converts seeking to immigrate from overseas were targeted by both the government and the press.

“The parallels between the Mormon experience and this case are surprising,” the brief states. “Using language one might hear today about unpopular immigrant groups, 19th-century officials described Mormons as ‘a community of traitors, murderers, fanatics, and whores.’

“Politicians and the press explicitly compared Mormons to Muslims and ‘Orientals,’ viewing them as ‘distinct, peculiar, suspicious, and potentially dangerous outsiders,’” the brief adds.

It concludes by asking the high court to “subject [Trump’s executive order] to close scrutiny for a religious animus to prevent repeating the harms of the past.”