The Department of Justice made a more detailed request of a federal judge in Idaho last week to dismiss a lawsuit from an environmental law firm, one of several tied to the monument reductions. Forcing the documents to be made public "would disrupt the president's ability to carry out his constitutional responsibilities," the filing says.
Justice Department attorneys also said that their release would disrupt the attorney-client relationship between the department's Office of Legal Counsel and its clients in the executive branch.
The Boise-based firm Advocates for the West sued for 12 documents withheld from a public records request related to Trump's decision to reduce two sprawling monuments in Utah. He also is considering scaling back other monuments.
The documents written during the Barack Obama and George W. Bush administrations may justify why those former presidents made the monuments as large as they did and thus undercut Trump's plans to shrink them, the firm said.
"There is no legal authority for what (Trump) did in early December," said Advocates for the West attorney Todd Tucci. "These 12 documents will eviscerate any argument that his minions have concocted in the last month and a half. That's why they're hiding it."
Previous presidents created national monuments under the 1906 Antiquities Act, which sets guidelines calling for the "smallest area compatible with proper care and management of the objects to be protected."
Trump has said the monuments to be downsized are much larger than required in the Antiquities Act.
It's not clear what particular monuments might be mentioned in the documents. Tucci said the timing of the Bush administration document appears to be related to the 2006 designation of a marine monument that includes islands and atolls in Hawaii and a large expanse of ocean. Obama expanded the monument in 2016.
An email to Justice Department spokeswoman Sarah Sutton seeking comment on the documents, including whether any were written by the Trump administration, wasn't immediately returned Tuesday.
The Trump administration is facing other lawsuits from conservation groups, tribes and outdoor retail company Patagonia over the monument reductions. The groups argue that the president exceeded his power and jeopardized protections for irreplaceable archaeological sites and important lands.
Trump said he was reversing federal overreach and acted within his authority. Past presidents have trimmed national monuments 18 times, but there's never been a court ruling on whether the Antiquities Act also lets them reduce one.
The five separate lawsuits are in the early stages, with attorneys arguing over whether the cases should be handled in Washington, D.C., where they were filed, or moved to Utah at the request of the U.S. government.
Tucci said he doubts those lawsuits will lead to any of the 12 documents becoming public. He said a decision in the Idaho case could happen in May.
John Freemuth, a Boise State University environmental policy professor and public lands expert, said shrinking monuments is as much a political question as a legal question and could have big ramifications however it turns out.
"The big argument is whether the president has the authority to do this and what arguments the president is using," he said. "It's kind of in breath-holding mode now."
Associated Press writer Brady McCombs in Salt Lake City contributed to this report.
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