Documents sought under the Freedom of Information Act were withheld by the Interior Department under a practice that allowed political appointees to review the requests, internal emails and memos show.

The policy allowed high-ranking officials to screen documents sought by news organizations, advocacy groups and whistleblowers, including files set to be released under court deadlines. In some cases, the documents’ release was merely delayed. In other cases, documents were withheld after the reviews.

CQ Roll Call first reported on the “awareness review” policy in May, but a new trove of emails show documents were plucked from release following the screenings.

Liz Hempowicz, director of public policy for the Project on Government Oversight, a nonpartisan watchdog, said after reviewing some of the emails that Congress should investigate if Interior is violating FOIA.

“Are there bad actors at these agencies that are willfully ignoring the law?” Hempowicz said. “I think we need to get to the bottom of why it’s happening and that’s going to instruct how to fix it.”