The fight over the D.C. private school voucher program, the only federally funded program of its kind, is heating up as the Trump administration wants to double the size of the program while House Democrats scrutinize its operations.

The program, created by a Republican-controlled Congress in 2004, uses federal tax dollars to pay tuition at private and parochial schools for low-income District students. It has been lauded by conservatives, including Education Secretary Betsy DeVos, who say voucher programs provide alternatives for children stuck in failing public schools.

Most Democrats, including Del. Eleanor Holmes Norton, the District’s nonvoting representative, oppose private school vouchers, saying public dollars should flow to public schools.

D.C. Mayor Muriel E. Bowser (D) and D.C. Council Chairman Phil Mendelson (D) support the program because it also supplies additional federal funds to the city’s public schools, including charters.

The House Oversight and Reform and Education and Labor committees, joined by Norton, wrote to DeVos last week seeking detailed information about the program.

President Trump’s proposed fiscal 2020 spending plan would double the current budget of $45 million to $90 million — money that is equally divided among the private school vouchers, the traditional public schools and public charter schools in the city. The boost in funding for vouchers is setting up a showdown with House Democrats.

Lawmakers said they want to ensure that federal civil rights laws and safety regulations apply to students in the program, according to the three-page letter to DeVos from Oversight Committee Chairman Elijah E. Cummings (D-Md.), Education Committee Chairman Robert C. “Bobby” Scott (D-Va.) and Norton.

They requested details about schools participating in the program, including whether they are accredited, whether they are religiously affiliated, how much of their funding comes from the voucher program, whether they have tested drinking water for lead, how many students are disabled and English-language learners, and how many students did not graduate or transferred to another school.

DeVos, who spent three decades supporting the expansion of state-level voucher programs, considers the D.C. program a success.

“However, for far too long, the program has been used as a political football, leading to unpredictability in funding,” Education Department spokeswoman Liz Hill said in a statement. “The Secretary believes [program] funding should be increased to meet growing demand for the scholarships, and that the program should be supported at predictable levels for the future.”

Norton would like to allow the 1,500 low-income children who attend private and parochial schools using public funds to complete their education but stop new enrollments.

Democrats took the same approach in 2010, the last time they controlled the House. “I want to make this the beginning of the end for private school vouchers, while protecting the students who are now using those vouchers,” she said in an interview.

A 2012 Washington Post investigation found that hundreds of students use their voucher dollars to attend schools that were unaccredited or were in unconventional settings, such as a family-run K-12 school operating out of a storefront, a Nation of Islam school based in a converted Deanwood residence and a school built around the philosophy of a Bulgarian psychotherapist.

But Bowser and other city leaders have avoided criticizing the vouchers program because eliminating it could jeopardize funding for public and charter schools.

The program “has been instrumental in supporting the District’s three-sector approach on education by providing more opportunities and choices for our students and families,” Bowser spokeswoman LaToya Foster said in a statement. “We have called on Congress to reauthorize and fully fund [it] so that we have the resources we need to continue ensuring every family in every neighborhood has a fair shot at high quality educational opportunities.”

Mendelson declined to comment through a spokeswoman.

In 2010, the Education Department released a study that found voucher students were more likely to graduate than peers without vouchers, based on data collected by families. But the study found no evidence that the program improved math and reading scores.

Unlike public and charter school programs, there is little public oversight of the private and parochial schools in the voucher program, Norton said.

“We are continuing to send children with no idea how they are doing,” Norton said. “I certainly could see it not reauthorized if the data shows the program is not living up to its promise.”

Schools that accept vouchers are required to hold a certificate of occupancy and employ teachers who are college graduates, but they do not have to be accredited.

Norton noted that in 2016, Sen. Ted Cruz (R-Tex.) and Rep. Mark Meadows (R-N.C.) introduced legislation to force the District to use local tax dollars, not federal money, to fund the school voucher program. That legislation went nowhere.

Since 2004, Congress has appropriated more than $200 million for the program, according to the House committees’ request.