For families with disabled children, few federal laws are as important as the Individuals With Disabilities Education Act, known as IDEA. It’s the law that grants children with disabilities the right to attend public school. It also mandates that schools provide them with the services necessary to achieve success in that setting — in the same classrooms as non-disabled kids, whenever possible.

During Tuesday’s confirmation hearing for Betsy DeVos, President-elect Donald Trump’s nominee to run the US Department of Education, DeVos appeared to be unfamiliar with the law at the most basic level.

First, in a series of responses to questions from Sen. Tim Kaine (D-VA) on the rights of students with disabilities under IDEA, DeVos stated: “That is a matter that is best left to the states.” Then she went on to refer to a Florida program that encourages parents of children with disabilities to sign away their IDEA rights in exchange for a voucher for a private school.

Sen. Maggie Hassan (D-NH), who has a son with cerebral palsy, was unwilling to let the matter go. She returned to the issue, asking flatly whether DeVos knew that IDEA was federal law — and that states were bound by it. DeVos backtracked, stating that she “may have confused” the law with something else.

This left people with disabilities, family members, and educators confused as to whether DeVos was simply unaware that IDEA existed, or perhaps was not committed to enforcing the law in states and districts that don’t comply with it. It is hard to say which prospect is more disconcerting. On Twitter, the disability community reacted harshly:

DeVos literally didn't know what IDEA was. How can an Education Secretary not know about disability rights in education? — Jordan V. Allen (@jordanvalallen) January 18, 2017

Smokescreen! Devos has to know about IDEA, like Sessions she just doesn't support basic disability access laws. https://t.co/2haKahqkIA — Maig Bergio (@nut_maig) January 18, 2017

Essential background for understanding the ire of the disabilities community

Prior to the 1975 passage of the law that would evolve into IDEA (the Education for All Handicapped Children Act), only one in five students with disabilities received a public education. Many states actually had laws on the books explicitly excluding students with certain disabilities from enrolling in their school systems.

This began to change with a series of federal court cases in the early 1970s — most notably PARC v. Pennsylvania and Mills v. District of Columbia — that ruled that students with disabilities had a constitutional right to receive a public education. The court rulings prompted Congress to intervene in order to establish a federal framework for codifying and enforcing these rights; those efforts led to IDEA.

The law gives such students two key rights: a) the right to a “free and appropriate public education,” and b) the right that this education should take place in the “least restrictive environment” possible. The first provision means that students with disabilities are guaranteed access to a public education and that schools must provide necessary accommodations, services, and auxiliary supports. The second means that schools must provide that education and any accompanying services in the same classroom in which non-disabled students learn whenever possible. When that’s not possible, segregated settings should be resorted to only to the minimum degree required by the student’s disability.

To facilitate these rights, students receive an Individualized Education Program (IEP), a legal document that lays out how public education will be tailored to their needs. Once a year, families, students, school officials, and experts gather around a table to update the IEP and determine the child’s needs for the coming school year. The IEP lays out the accommodations a student may get in the classroom, and any additional related services the school will pay for, such as occupational therapy or speech pathology services. The IEP can even be used to pay for certain kinds of private school education — in the event the family requests it and the IEP team determines that it is the most appropriate placement for the child. Receipt of an IEP also comes with other educational rights, including protections against long-term suspension as a result of disability-related behavior.

For students with disabilities and their families, IDEA is the bread and butter of their educational careers. Without it, students with disabilities might not have the right to even attend public school, much less get the services necessary to make that a meaningful experience. Most people with disabilities born within the past four decades recall receiving an IEP during their own time in school. I recall the IEP process very vividly myself, and how important it was to making sure I had a chance to receive the same opportunities as students without disabilities.

As of 2014, 13 percent of students in US public schools had an IEP — though the number varies by state. Massachusetts offers an IEP to 17.5 percent of its youth with disabilities, while Texas — notorious for being poor at identifying and serving Hispanic students with disabilities — offers an IEP to only 8.6 percent of its students.

Outcomes also vary significantly within states, with some districts and individual schools manifesting abysmal educational achievement for students with disabilities and high rates of segregation. These kinds of inequities across states are a significant concern to disability rights advocates — and part of why the prospect of a Secretary of Education who does not seem committed to enforcing civil rights law for students with disabilities is so disturbing.

Conservatives use students with disabilities to push voucher programs

There is a further unsettling subtext to DeVos’s comments about IDEA.

Earlier in the hearing, Sen. Lamar Alexander (R-TN) had referred to legislation he had introduced — it failed to pass — enabling states to turn Title I federal education aid for low-income schools into private-school vouchers. Alexander noted that after its failure, Sen. Tim Scott (R-SC) introduced similar legislation, also voted down, to do the same for federal IDEA funding.

This trajectory is a not-unfamiliar one. In many states where school voucher programs have been met with skepticism, proponents have sought to use vouchers targeted specifically to students with disabilities as a starting point to open the conversation about the merits of using public money for private education. As a result, Florida, Ohio, Georgia, Louisiana, Oklahoma, and Utah, among other states, all have special-education voucher programs. In most of these, parents who accept a voucher waive their rights under IDEA. They can use the money to send their children to a private school — assuming they can afford it — but they can no longer demand the rights and legal protections established by IDEA: free education in the least-segregated environment possible.

This is the backdrop to yesterday’s exchange on IDEA rights: an ongoing conservative effort to use students with disabilities as the tip of the spear for promoting vouchers.

Advocates are concerned by these voucher programs, both because of the requirement that parents waive educational rights, and because of the lack of any sort of framework to hold private schools accountable for their treatment of disabled youth. Voucher students are not typically included in state assessments, and the schools that participate in special education voucher programs often lack accreditation requirements or curriculum standards. In one school participating in Florida’s special education voucher program — the oldest in the country, briefly referenced by DeVos at the hearing — a local newspaper’s investigation found widespread use of corporal punishment. The school also offered a “business management” class that consisted of shaking cans on street corners for coins.

Given that most of the private schools accepting special education vouchers are designed specifically for disabled students, there is also a fear that the proliferation of these programs will cause students with disabilities to lose hard-earned progress in accessing the general education classroom. School districts that become used to the presumption that students with disabilities belong in special-education schools may no longer invest in supporting students with more complex needs in inclusive settings.

People with disabilities and their families fought long and hard to establish the educational rights reflected under IDEA. The prospect of an education secretary who does not recognize the importance of those rights — because of ignorance or ideology — is terrifying to them.

To some, this calls forth the memory of the Reagan administration’s effort to roll back IDEA shortly after Reagan entered office — an attempt that was met with a massive response from tens of thousands of furious youth, parents, and advocates. If the Trump administration decides to pick a similar fight, expect disability rights advocates to show up in force to respond.

Ari Ne’eman is the CEO of MySupport.com, an online platform helping people with disabilities, seniors, and families to manage their in-home services. From 2006 to 2016 he served as president of the Autistic Self Advocacy Network, and from 2010 to 2015 he was one of President Obama’s appointees to the National Council on Disability.

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