The Obama administration said it applied to all public schools as well as colleges and universities that received federal funding. The directive "summarizes a school's Title IX obligations regarding transgender students," administration officials said, and that it also explained how the Education and Justice departments will "evaluate a school's compliance with these obligations."

The federal Title IX statute prohibits sex discrimination in educational programs and activities, like sports. Some months before issuing the directive, Obama administration had warned schools that denying transgender students access to the facilities and activities of their choice was illegal under its interpretation of federal sex discrimination laws.

Officials at the Justice and Education departments in the Trump administration rejected the previous administration's position that nondiscrimination laws require schools to allow transgender students to use the bathrooms of their choice.

That directive, they said, was arbitrary and devised "without due regard for the primary role of the states and local school districts in establishing educational policy."

"Pope Francis has taught that 'biological sex and the sociocultural role of sex (gender) can be distinguished but not separated," said Archbishop Chaput and Bishop Murry, quoting from "Amoris Laetitia," the papal document on marriage and family.

"The Catholic Church consistently affirms the inherent dignity of each and every human person and advocates for the well-being of all people, particularly the most vulnerable," the two prelates said. "Children, youth and parents in these difficult situations deserve compassion sensitivity, and respect. All of these can be expressed without infringing on legitimate concerns about privacy and security on the part of all young students and parents."

A new poll shows that a majority of U.S. adults, 56 percent to 38 percent, disagree with allowing transgender individuals to use whatever public school bathroom that they want to use. When asked if that choice should extend to use of a public school shower or locker room, 66 percent overall disagreed, 27 percent agreed.

The Marist Poll partnered with Crux, an online news site specializing in coverage of the Vatican and the Catholic Church, to conduct a survey of 545 adults selected at random and ranging in age from 18 to 60 or older and living in the contiguous 48 states. The margin of error for the total sample was plus or minus 4.2 percentage points. Respondents were surveyed by landline or cellphone Dec. 12-13.

Broken down by political party affiliation, 36 percent of those who self-identified as Democrats said they disagreed with transgender individuals being allowed to use the public school bathroom of their choosing, while 56 percent agreed. Of those who said they were Republicans, 81 percent disagreed, while 16 percent agreed. Among Independents, 52 percent disagreed, 41 agreed.

Among white respondents, 55 percent disagreed, while 39 percent agreed. Of Latino respondents, 63 percent disagreed and 35 percent agreed. Forty-nine percent of all those under 45 disagreed, 47 percent agreed; of those 45 and older, 63 percent disagreed, and 30 percent agreed. For those 60 and older, 59 percent disagreed, 33 percent agreed. In the 18 to 29 age group, 45 percent disagreed, 49 percent agreed.

Among men, 63 percent disagreed, 32 percent agreed; and of women, 49 percent disagreed and 44 percent agreed.