More than 150,000 former students of for-profit colleges filed a lawsuit against the U.S. Department of Education and Education Secretary Betsy DeVos on Tuesday, claiming the agency is depriving them of the student debt relief to which they're legally entitled.

The plaintiffs, represented by Harvard Law School's Project on Predatory Student Lending and Housing & Economic Rights Advocates, accuse the Department of Education under DeVos of failing to implement an Obama-era regulation known as "borrower defense," which allows students to have their federal student loans cancelled if their school misled them or engaged in other misconduct.

"The law is clear: Students who experienced fraud should not be required to pay back federal loans that should never have been made by the Department in the first place," said Toby Merrill, director of Harvard Law School's Project on Predatory Student Lending.

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Around 160,000 people have filed claims with the government that their school defrauded them, and new applications continue to pour in. Almost all of these complaints concern for-profit schools, of which there are some 7,000 around the country and which take in around 15% of government financial aid.

However, student loan borrowers have found themselves waiting without answers. The Department of Education hasn't approved or denied a borrower defense claim since June 2018.

An audit in 2017 by the Department of Education's Office of Inspector General found that government staff working on borrower defense claims had been instructed not to submit any additional applications for approval.