This story was originally published by Reveal from The Center for Investigative Reporting, a nonprofit news organization based in the San Francisco Bay Area. Learn more at revealnews.org and subscribe to the Reveal podcast, produced with PRX, at revealnews.org/podcast. House Democrats grilled Interior Secretary Ryan Zinke this week about National Park Service officials deleting all references to the human cause of climate change in drafts of a long-awaited report. Zinke told a House Appropriations subcommittee on Wednesday that he and other political appointees at the Interior Department, which oversees the Park Service, have not seen the draft. And he repeated a vow that he will not censor scientific reports.