Washington (CNN) There's a fight brewing between states and Secretary of Education Betsy DeVos over who has the power to police student loan servicing companies as consumer advocates question whether the federal government is doing enough to protect borrowers from shady practices.

Democratic attorneys general from 20 states and Washington, DC, sent a letter to the secretary last week saying the Department of Education is blocking access to records requested by law enforcement.

"The department's policy reversal impedes states' ability to enforce the law and shields unprincipled industry actors from regulatory enforcement, harming student loan borrowers nationwide," the letter reads.

The department has cited privacy reasons when rejecting requests for information over the past year, the attorneys general wrote.

The Department of Education argues that it's best for the federal government to monitor the system -- a departure from DeVos' stance about state power on other education issues. She's argued that it should be left up to the states to decide whether teachers have guns in the classroom and to set discrimination rules for private schools that receive public funding.