Sen. Elizabeth Warren has added details to her far-reaching plan to forgive college student debt and called for an investigation of racial disparities in how much students borrow.

The update outlines how she would implement her campaign proposal to cancel up to $50,000 in debt for 42 million people. Her proposed wealth tax on the 75,000 richest families, the campaign has said, would cover the cost.

The latest plan, released Tuesday on Warren’s campaign website hours before the first Democratic primary debate of 2020, maintains the U.S. Department of Education has the “broad legal authority” to cancel student debt under the Higher Education Act of 1965.

That authority is said to enable Warren as president to direct the education secretary to begin reducing outstanding student loans.

A legal analysis from a trio of attorneys with the Project on Predatory Student Lending at Harvard Law School argues that the debt reduction directive would hold up in court based on a web of regulations that guide the secretary’s authority to modify existing student loans. Eileen Connor, Deanne Loonin and Toby Merrill signed a review that concludes the proposal “calls for lawful and permissible use of authority” that Congress has already given to the secretary.

The plan also contains a vow to have the department’s Office for Civil Rights undertake a “wide scale” investigation into “the roles that colleges, state higher education systems and the student loan industry play in contributing to racial disparities in student borrowing and student loan outcomes.”

“Experts have pointed to the racial wealth gap and racial discrimination in the labor market as potential contributors to the disparities in student debt,” the proposal notes, “but there has been little investigation into how the fundamentals of the provision of student loans — from the way our higher education system is organized to the practices of student loan servicers and debt collectors — contribute to the racialized outcomes of the student loan program.”

The proposal brings the count of Warren’s campaign plans to 70 and builds on an earlier, broader call for affordable higher education.