This week, President Trump signed two proclamations, which reduced the size of two national monuments in Utah by 2 million acres and is now the largest rollback of federal land protection in U.S. history. Using the Antiquities Act, Trump formally downsized the Grand Staircase-Escalante Monument to about half its size (from 1.9 million acres to just over a million acres) and reduced Bears Ears Monument by 85 percent (from 1.35 million acres to less than 202,000 acres). The move comes as the Trump administration seeks fewer restrictions and more development on public lands.

Bears Ears has attracted controversy since 2016, when President Obama initially declared that the 1.35 million acres in southeastern Utah would become a national monument. In April, President Trump first ordered Secretary Zinke to review 27 national monuments that had been created since 1996 and Secretary Zinke delivered a report in August suggesting President Trump alter the boundaries of several monuments. President Trump argued that previous presidents overstepped their authority under the Antiquities Act, which mandates that national monuments be “confined to the smallest area compatible with proper care and management of the objects to be protected.” President Trump’s order explicitly notes that the new boundaries will be consistent with that standard.

Soon after the announcement, five Native American tribes sued the Trump administration and several more lawsuits have since been filed by conservation, historical, and outdoor industry groups. Environmentalists and tribes say that Trump’s decision will destroy the national heritage and threaten some 100,000 sites of archaeological importance in the monuments’ desert landscapes. On the other hand, conservative lawmakers and many Westerners argue that the reduction is the property response to decades of federal overreach that starves communities of revenue and autonomy. For example, when President Clinton formed the Grand Staircase, it halted plans for a coal mining project that would have brought desperately needed jobs to a poor county.

Previous presidents have made similar reductions to national monuments. For example, Woodrow Wilson reduced Mount Olympus by half and Franklin Roosevelt cut the Grand Canyon monument at the behest of ranchers. Both are now national parks. However, it is important to note that the courts have never ruled on whether a president has the power to make these types of changes so these lawsuits will likely have wide implications.