Education Secretary Betsy DeVos testifies before the Senate Appropriations Committee on Tuesday. DeVos testified on the fiscal year 2018 budget request for the Education Department. Win McNamee

Over and over again, Education Secretary Betsy DeVos deflected a barrage of pointed questions with one answer:

"Schools that receive federal funds must follow federal law."

Appearing Tuesday before a Senate Appropriations subcommittee, DeVos was asked repeatedly by lawmakers if, under a federal voucher program, she would prohibit private schools from discriminating against LGBTQ students and children with disabilities. Recent reports, including an NPR investigation of Indiana's voucher program, have documented private schools excluding these students.

When Democratic Sen. Patty Murray of Washington asked if private schools would be required to follow IDEA, the federal Individuals With Disabilities Education Act, DeVos began the pattern:

"Any institution receiving federal funding is required to follow federal law."

When Murray followed up, she got the same answer, again.

Later, Sen. Jeff Merkley, an Oregon Democrat, pointed out that federal anti-discrimination laws are "somewhat foggy" and asked DeVos if private schools that take federal dollars should be allowed to turn away LGBTQ students.

"Senator, I said it before and I'll say it again, that schools that receive federal funds must follow federal law," DeVos replied.

Later in the hearing, when Democrat Jack Reed of Rhode Island picked up the anti-discrimination thread, DeVos repeated the answer eight more times. At one point Reed, exasperated, asked: "But what does that mean?"

Now that's a good question.

LGBTQ students

No current federal law explicitly protects the rights of LGBTQ students. Put another way:

"The current state of federal protections for LGBTQ students is ambiguous," says Nathan Smith, director of public policy at GLSEN, a group that champions LGBTQ issues in K-12 education.

That ambiguity stems from this sentence in the law known as Title IX of the Education Amendments of 1972:

"No person in the United States shall, on the basis of sex, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any education program or activity receiving Federal financial assistance."

A debate has raged through U.S. courts around whether "sex" includes sexual orientation and gender identity.

"The majority view of the courts right now is that transgender students are protected from discrimination by Title IX," says Seth Galanter, a former senior official in the Education Department's Office for Civil Rights under President Barack Obama. "The courts are more divided about whether LGB students are protected by federal law from discrimination. But there is a trend in the lower courts that they will be protected."

In an attempt to clarify this ambiguity, the departments of Education and Justice under Obama issued a "Dear colleague" letter, telling districts that Title IX's prohibition on sex discrimination "encompasses discrimination based on a student's gender identity, including discrimination based on a student's transgender status." In February, the Trump administration rescinded that guidance (a move DeVos reportedly opposed.)

Further complicating matters, Title IX includes an exemption for private schools that are run by religious organizations, as is the case with many current voucher-accepting private schools.

So when it comes to a hypothetical federal voucher system, says Galanter, that "makes the question about whether Title IX prohibits discrimination against transgender kids or LGB kids kind of irrelevant."

In short, when DeVos says, "Any institution receiving federal funding is required to follow federal law," it's important to know that that law offers limited protections for LGBTQ students and an exemption for many schools.

Students with disabilities When it comes to protecting students with disabilities from discrimination, schools take their cues from three separate federal laws: the Americans With Disabilities Act, Section 504 of the Rehabilitation Act of 1973, and the Individuals With Disabilities Education Act. But civil rights experts say that, in a hypothetical federal voucher system, none would offer strong guardrails.

First, the ADA. Like Title IX, it includes an exemption for private, religious schools and thus limited protection in a voucher system.

Section 504 does not offer religious schools an exemption and would likely provide students with disabilities some protections from discrimination in a federal voucher program. But, says Galanter, "It generally is a low bar." That's because the law only requires that private schools that receive federal funds make "minor adjustments" to accommodate students with disabilities.

"Those schools must provide reasonable accommodations" for students with disabilities, says Julie Mead, a professor in the Department of Educational Leadership & Policy Analysis at the University of Wisconsin-Madison. "But they do not have to alter their existing programs or add anything to them. What that means is, if their existing program does not provide any special education or related services, then they don't have to provide any."

As for IDEA, the federal law that Sen. Murray invoked at the start of Tuesday's hearing, students with disabilities enjoy few if any protections once their parents voluntarily enroll them in a private school. If a student is placed in a private school by a public school that cannot serve her needs, then the child is still guaranteed a Free Appropriate Public Education. But that protection requires that parents work through the public school system.

At the end of a heated exchange with Oregon's Sen. Merkley, DeVos broke briefly from her line about federal law to assure lawmakers that "discrimination in any form is wrong. I don't support discrimination in any form."

What's not clear is how the Education Department would prevent discrimination in a federal voucher program, given the current limitations of federal law. Copyright 2019 NPR. To see more, visit https://www.npr.org.