Despite being 112 years old, the Antiquities Act remains a significant source of controversy and conflict. For supporters, its expansive interpretation provides a necessary tool to protect the environment and avoid the congressional gridlock that leaves sensitive federal lands vulnerable. Opponents of the way the law is currently implemented respond that its loose wording has invited significant abuse, with presidents claiming nearly unchecked power over unlimited stretches of federal lands and seas. Opponents also decry the lack of procedural protections to insure public or legislative input and accountability.

This conflict has been growing more heated in recent years, as presidents have been more aggressive in their use of the law. President Theodore Roosevelt was criticized for the scope of some of his national monuments, but he was a piker compared to recent presidents of both parties. Consider the data: it took a century for Presidents Teddy Roosevelt through Clinton to designate about 70 million acres of national monuments; yet, in a mere sixteen years, Presidents George W. Bush and Obama added more than 700 million acres to this total.

This exponential spike in the area covered in the law’s second century is made more surprising by the fact that federal law has evolved significantly. In 1906, there were few federal laws directed at protecting federal lands, resulting in the Antiquities Act serving as the main tool for this purpose. But since the 1970s, Congress has enacted a smorgasbord of environmental and federal land statutes, making the Antiquities Act far less important today except with respect to a narrow category of historic landmarks, historic homes and battlefields, and true antiquities. Why then is the Antiquities Act still used for vast park-like designations? The most likely explanation is that the more modern statutes, unlike the Antiquities Act, contain substantive and procedural limits that constrain executive authority. Such limits obviously hold little appeal to the executive being constrained, but are nonetheless essential to the Constitution’s separation of powers.

The latest Antiquities Act conflict is over President Trump’s decision, on December 4, 2017, to reduce the size of two monuments in Utah: Bears Ears National Monument and Grand Staircase-Escalante National Monument. Fans of irony will appreciate how the two sides to this long-running conflict promptly adopted some of their opponents’ arguments. Supporters of the President’s decision—including many who have criticized recent Antiquities Act abuse—praised the decision as a wise use of the President’s broad power. Opponents of the decision—including a variety of interest groups that have defended past Presidents’ aggressive use of the law—now decry the lack of statutory standards and public process to limit the President’s actions.

Within a week of the President’s announcement, five lawsuits were filed by environmental activists, Indian tribes, and at least one outdoor gear company. Our Foundation was among those that intervened to defend the President’s authority. Those cases all raise an issue that, surprisingly, remains unresolved despite the statute’s age: Does the Antiquities Act permit the President to revoke or reduce an existing national monument, or is it a one-way ratchet?

Professor John Yoo and one of us answer this question definitively in our Yale Journal on Regulation article, Presidential Authority to Revoke or Reduce National Monument Designations. The article’s central scholarly contribution is to identify an important principle of American law: where a government branch or official is given a broad discretionary power, in the Constitution or a statute, it also includes the power of amendment or reversal by following the same procedure used to give the original decision effect. There are only a few special exceptions to this principle, which exist only when reversal is impossible, when unalterable private vested rights have been created, as with a presidential pardon, or when the original grant of power expressly provided for another means of amendment—such as Article V in the U.S. Constitution itself.

Thus, the President clearly has the power to remove officers, even though the Constitution only expressly addresses his power to appoint them. And Congress can repeal statutes even though the Constitution is silent about repeal and the process Congress must use to affect it.

Likewise, the United States Code is replete with hundreds of regulatory statutes, many of which are also for a protective purpose, authorizing agencies to issue regulations but saying nothing about subsequent amendments or repeals, yet courts routinely uphold such revisionary powers.

Pursuant to this strongly entrenched principle of law, the parties opposing President Trump’s decision to shrink the monuments face an uphill slog. By claiming that presidents can vastly expand national monuments but cannot repeal or significantly shrink any, they are essentially arguing that the Antiquates Act is alone among all federal statutes in how it operates. Their argument is made even more difficult by the failure to identify a single case where any court has held that a statute granting an executive official broad authority also silently withheld the authority to reconsider its exercise. Thus, to prevail, the challengers must convince the courts that Congress set aside this principle for the Antiquities Act and that: (1) it did so with no express text, which would be unprecedented, (2) without anyone in Congress noticing or commenting on this aberration at the time, and (3) that it continued to go unnoticed for over 110 years.

Historical practice makes that last claim particularly dubious. Since 1906, Presidents of both parties have significantly reduced national monuments established by their predecessors. In doing so, they’ve cited the full gamut of justifications for the reductions, including economic benefits. And several of the reductions have been especially large; the greatest percentage change was an 89% reduction of the Navajo National Monument by President Taft, who was in Teddy Roosevelt’s cabinet when the Antiquities Act was enacted.

That the President can reduce or revoke a national monument does not mean that federal lands can’t be permanently protected. In our constitutional system, the only relatively permanent protections are contained in duly enacted laws, which require a high level of political consensus (itself a protection against arbitrary government) and representative accountability, consistent with constitutional formalities. None of that is required by the Antiquities Act.

Whereas national monuments can be established or revoked by the mere stroke of the President’s pen, national parks require an act of Congress, both to create and to change. Thus, the difficulty of reducing protections is directly tied to the difficulty of establishing them in the first place. If the President’s power to reduce a national monument has caused alarm, it may be a sign that federal-land advocates have too often taken the easy road rather than looking to build consensus in Congress.

If the courts uphold the President’s power to revoke or reduce national monuments, as we predict, that could have the happy benefit of encouraging federal-land advocates to turn their focus to Congress. Congress might be convinced that some of these areas should be established as national parks or other statutory protections. In fact, many of our most popular parks began as national monuments.

But the greatest potential is for reform of the Antiquities Act itself. Once it is clearly established that the Antiquities Act’s broad, standard-less, and procedure-less power cuts both ways, there may finally be an opportunity to reform the Antiquities Act and reduce future conflict.

Todd Gaziano is Pacific Legal Foundation’s Chief of Legal Policy and Strategic Research and the Director of PLF’s Center for the Separation of Powers; he is the co-author of the Yale Journal on Regulation article discussed above. Jonathan Wood is a Pacific Legal Foundation attorney and a research fellow with the Property and Environment Research Center. In addition to their involvement in the national monument litigation in Utah, Gaziano and Wood also represent commercial fishing organizations challenging the creation of the Northeast Canyons and Seamounts Marine National Monument.