WASHINGTON, D.C. – U.S. Sen. Elizabeth Warren has spoken out against President-elect Donald Trump’s pick for Secretary of Education, Betsy DeVos, because of the Michigan philanthropist’s support for school vouchers.

And while Warren is expected to grill DeVos before the Health, Education, Labor and Pensions committee on Tuesday over her long-standing support for school choice, some are highlighting that Warren herself has promoted vouchers as a means of fixing the problems that have plagued public schools for decades.

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Hillary Chabot, a columnist for the Boston Herald, pointed out Monday that Warren wrote about school vouchers in a 2003 book she authored with her daughter titled “The Two-Income Trap.”

According to Chabot:

“An all-voucher or all-school choice system would be a shock to the educational system, but the shake out might be just what the system needs,” Warren wrote in a book she co-authored with her daughter, Amelia Tyagi.

The Harvard Law professor proposed giving students vouchers to attend any public school they wanted in an attempt to eliminate the current system that often necessitates that students live in a pricey community to attend a good public school.

“The whole concept of ‘the Beverly Hills schools’ or ‘Newton schools’ would die out,” she wrote of the vouchers.

Warren’s position on school choice shifted over time, however, and she recently opposed a ballot question that would increase the number of charter schools in Massachusetts. Now Warren and other Trump critics have blasted DeVos for backing a school voucher system that would allow students to attend private schools at public expense.

DeVos is among a growing number of school choice advocates who believe that providing school vouchers to students to attend public or private schools would push all schools to improve academics by creating much-needed competition.

The free-market approach would shift decision-making power from education bureaucrats with a vested interest in maintaining the public school monopoly they depend on for their livelihood to parents whose only interest is the quality of education their children receive.

With vouchers, parents would determine the best school for their children, and direct their funds to those schools, a reality that would force poorly performing schools to improve or close down. Warren’s support for school choice seems to have been limited to only public schools, but applies the same concept, nonetheless.

The difference between Warren’s past support for public only vouchers and DeVos’ longstanding support for universal vouchers seems to hinge on one key aspect: the Harvard law professor doesn’t seem to trust parents to decide the best option for their child, while DeVos does.

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Warren seems to think the government, and the teachers unions who help to elect Democratic lawmakers, know what’s best, while DeVos believes parents are smart enough to hold schools accountable.

“You and the organizations you led have also spent millions to promote policies that send more public funds to for-profit and virtual charter schools with no accountability for how well these schools serve students or how these taxpayer dollars are spent,” Warren wrote in a 16-page letter to DeVos last week, according to The Hill.

Because DeVos is a lifelong school choice advocate and mother, rather than an education bureaucrat, she doesn’t deserve to lead the nation’s education system, Warren argued.

“While past nominees for secretary of Education have served as teachers, school system leaders, and governors, and came to the Department of Education with deep executive experience in public education, you have held no such position,” she wrote.