Almost from the day he took office, President Donald Trump’s environmental agenda has put the profits of big corporations ahead of the public interest.

While Interior Secretary Ryan Zinke pays lip service to balanced uses of public resources, Trump and his administration have overwhelmingly sided with polluting industries who prefer unchecked resource extraction with minimal public oversight.

The Trump approach to public lands has been little more than a parade of handouts to corporate executives and lobbyists who have the administration’s ear. One of the ugliest consequences is President Trump’s illegal destruction of Bears Ears National Monument and Grand Staircase-Escalante National Monument in southern Utah, where in a 2017 executive order he attempted to shrink monument boundaries despite lacking any authority to do so.

Let’s be clear: no president can unilaterally eliminate existing federal environmental protections on our public lands, however much President Trump may prefer otherwise. His action is clearly illegal, and allowing him to follow through on it would set a precedent that Americans of all political stripes should oppose.

That’s why, along with 118 of our colleagues — 26 senators and 92 representatives — we filed an amicus brief on Nov. 19 in the U.S. District Court for the District of Columbia arguing not only that these national monument boundary reductions are legally void, but that they clearly contradict congressional intent as expressed in the Antiquities Act of 1906, the law President Clinton used to create Grand Staircase-Escalante in 1996 and President Obama used to create Bears Ears in 2016.

This lawmaker coalition, which includes both House and Senate Democratic leadership, represents a strong congressional rebuke to the Trump administration’s insistence that public lands are rightfully the property of oil, gas and coal companies — and puts the administration on notice that it should expect strong oversight of its industry-first agenda in the next Congress.

Sixteen presidents — Republican and Democratic — have used the Antiquities Act for more than a century to protect precious places for future generations. The Constitution, in black and white, gives Congress the power to manage public lands. The president may not create new executive authorities as the need or desire may arise.

The Antiquities Act gives the president power to designate national monument boundaries on existing federal lands and waters. Congress gave the president that power, understanding that the legislative process can be slow and deliberative — and that many public lands and waters could be lost without swift action.

Nowhere does the Antiquities Act give authority to reduce boundaries, revoke monument status or otherwise reduce standing levels of protection.

Most federal cases deal in complicated questions of interpretation. The legal language at issue here is unusually clear.

We find it curious, therefore, that the Department of Justice has taken the unusual step of asking Judge Tanya Chutkan not to allow our filing to be included in the legal record of this case. As members of Congress, we have not only a clear interest in the outcome of the case but unique standing to intervene on behalf of congressional prerogatives. Allowing the executive branch to invent federal land use policy on the fly, outside the boundaries of federal law, is not just a terrible idea on the merits — it is a serious blow to the separation of powers.

This is not a Pandora’s box anyone of any party wants to open. If President Trump’s order stands, Republicans who support his environmental agenda today could face a sudden change of heart the next time a Democrat occupies the White House. In our minds, it is better to keep to the constitutional principles that have served us for centuries than to let a president decide which laws he does and doesn’t follow on a given day.

This is to say nothing of the merits of this specific case, which frankly do the administration no credit. The administration has long claimed the monument reductions were never about opening land to extraction. This doesn’t pass the straight face test, and we have already seen strong evidence to the contrary. Portions cut out of the monuments are known to be rich in oil, coal and uranium, and industry figures have filed claims on several parcels of land formerly within the monument boundaries. Feigning ignorance of these implications only weakens the administration’s case.

The bottom line is that national monuments enjoy overwhelming public support, and presidents have no power to revoke or shrink them with the flick of a pen. That power is simply not found anywhere in the law. The Trump administration does themselves no favors by claiming otherwise. If they wish to locate such power elsewhere, they should say so. If not, they should admit that President Trump’s actions were never legally supported, and that even industry-first administrations need to respect congressional intent, as our Framers made clear.

Sen. Tom Udall (D-N.M.) is ranking member of the Senate Appropriations Subcommittee on Interior, Environment, and Related Agencies. Rep. Raúl M. Grijalva (D-Ariz.) is ranking member of the House Committee on Natural Resources.

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