Assistant editor and Opinions contributor

Supreme Court Chief Justice John Roberts prior to President Obama’s State of the Union speech on Capitol Hill in Washington in 2014. (Larry Downing/Reuters)

Stop me if you’ve heard this one before: The 2016 election matters because the next president might be nominating two or three justices to the Supreme Court.

It’s one of those statements you hear all the time because, well, it’s true. The next Supreme Court appointment may throw the liberal vs. conservative balance of the court into disarray, which is why pundits have been issuing foreboding proclamations like “we’re only one vote away from losing (insert constitutional right here).”

One of the legal issues that’s less often discussed is the role that the next Supreme Court justice will play in conservatives’ long-running legal fight to limit the size of the federal government. For decades, conservatives on the bench have been losing that war, giving way to a system of administrative law that is written, for the most part, by bureaucratic agencies. Without putting a justice on the bench who can build consensus on how to rework the rules on agencies’ regulations, it’s likely conservatives will lose this fight in the long run.

Administrative law — the area of the law governing the rules and regulations created by federal agencies — is, especially in oral arguments, incredibly arcane. But philosophically speaking, it’s a really big deal. Over the past half century, agencies have exploded in size and power, so this debate really is about how much power the federal government should have.

The question of how they interpret federal statutes touches on some of the most high-profile cases in federal courts in recent years: the case on the president’s climate-change regulations (Massachusetts v. EPA), the Affordable Care Act ruling from 2015 (King v. Burwell), this year’s immigration case (United States v. Texas) and the transgender student case (G.G. v. Gloucester County School District), just to name a few.

It all rests on a relatively obscure law called the Administrative Procedure Act, passed by Congress in 1946. The APA, despite its terribly boring title, was probably one of the most important laws ever enacted, spelling out how federal bureaucrats are supposed to write the rules through which they enforce the law. In addition to requiring notice-and-comment periods for the public to review any formal rules (to preserve at least some semblance of democracy), the APA also gives guidelines to courts on how best to review these regulations.

For the most part, the courts have developed a system that grants a lot of leeway to federal agencies. Among legal pundits, the topic is referred to as “agency deference” (or “Chevron deference,” taken from a 1984 Supreme Court case, if you want to get even wonkier). The logic is pretty simple: Let the experts and regulators decide the tough questions, not judges. So long as Congress is silent or ambiguous on an issue and the relevant agency’s regulation is “reasonable,” then it will probably be able to pass muster in court.

This is how, for example, the EPA was able to classify carbon dioxide as an “air pollutant” that it can regulate under the Clean Air Act. Lawmakers gave the federal government the power to regulate air pollutants but remained fairly vague about which pollutants or how it should be done.

Conservatives, fearful that bureaucracies are becoming an unchecked “fourth branch of government,” have decried agency deference. Just last month, Justice Clarence Thomas argued that the doctrine “has metastasized,” as if it were a cancer. And back in 2013, Chief Justice John Roberts warned of the “danger posed by the growing power of the administrative state,” labeling Chevron deference as “a powerful weapon in an agency’s regulatory arsenal.”

Both Roberts and Thomas frame the issue as a threat to the separation of powers: We’re letting agencies in the executive branch dip into the powers reserved for the judicial and legislative branches. By letting agencies fill in the ambiguous holes left in laws by Congress, we give the executive branch authority to write new laws. And by allowing bureaucrats the ability to define the scope of their own jurisdiction, we let them answer questions meant to be left up to the courts. This, they argue, is at odds with the Constitution.

At the same time, though, the late Justice Antonin Scalia — an architect of Chevron deference — had long defended the framework that granted agencies power to interpret the law. Scalia used administrative law to help shape his vision for the role of the Supreme Court: an institution where its members did not project their personal beliefs onto the laws, limiting its scope to preserving constitutional rights. If an agency’s regulations are inadequate or incorrect, he would likely argue, Congress should put it to a vote.

It’s a fundamental philosophical conflict about how courts should review the law. And certainly over the past few decades, this friction between conservatives has allowed a number of cases to advance through the Supreme Court that gave greater power to federal regulators (although Scalia notably became uncomfortable in recent years with how far the court was willing to go). Without a consensus opinion to hold back the advance of agency deference, bureaucrats have become even more emboldened to formulate new rules and procedures. Adrian Vermeule of Harvard Law School recently showed just how pervasive agency discretion has become in administrative law.

Now that the court is evenly split between conservatives and liberals, it’s unclear what the future of administrative law will look like. But at the moment, those who care about the topic have been disheartened by Merrick Garland, Obama’s pick to fill Scalia’s vacancy, who has a history of deferring to agency interpretations.

Yet even if Republicans somehow get their preferred judges onto the bench in the next few years, rolling back agency deference still isn’t a slam-dunk. The Chevron decision is 32 years old, and since it was delivered, a host of decisions have reaffirmed agency deference, expanded upon it and used it as a cornerstone to propel administrative law. It would likely take multiple rulings and a solid conservative consensus over a number of years to reverse the direction in which the court has been heading.

And ironically, if Republicans won the election but somehow ended up with divided government, they might even push back against the effort. Faced with a bitterly divided government, the Obama administration has been grasping for unitary control of policy through administrative law. What would keep Republicans under a President Trump from doing the same?

Conservatives fearing a powerful bureaucratic state have few legal weapons to fight it. The future of a small-government Supreme Court is bleak, and the march toward greater agency control of the law will probably continue forward.

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