There’s a lot we don’t know for certain about Neil Gorsuch, President Donald Trump’s pick to be the next Supreme Court justice: for example, his exact views on abortion, gay rights, and affirmative action. But there’s one issue, virtually unnoticed by the public but huge in the legal community, where Gorsuch’s views are clear — and potentially critical for the future of government regulation and executive power.

At issue is a doctrine known as Chevron deference, named for the 1984 Supreme Court case Chevron v. Natural Resources Defense Council, which says that the courts will defer to regulatory agencies when they interpret ambiguous laws passed by Congress.

Chevron deference has been central point of dispute on a range of important issues, from network neutrality to immigration. And Gorsuch is a Chevron skeptic. As a member of the Supreme Court, he could push to narrow or even overturn the doctrine, leading to courts more aggressively second-guessing how agencies interpret laws passed by Congress.

That could be particularly significant in an era where partisan gridlock is making Congress less and less effective at its job. Chevron deference gives administrative agencies flexibility to adapt vague, decades-old laws to modern-day circumstances. But if Gorsuch sways a Court majority to his view, agencies might lose a lot of that flexibility in the coming years.

Chevron deference has created a decade of uncertainty in internet regulation

The debate over broadband regulation and network neutrality provides a good illustration of why Chevron deference matters. Until 2005, there was a growing market of independent internet service providers who provided internet service by leasing infrastructure from incumbent telephone companies at rates regulated by the Federal Communications Commission.

Advocates of an open internet wanted the FCC to impose the same rules on cable companies. Most cable companies were opposed to this.

The case turned on the definition of a key legal category: “telecommunications service.” If cable broadband internet was a telecommunications service, then the law required cable companies to rent their lines to independent ISPs. The FCC had decided cable broadband wasn’t a telecommunications service and exempted them from the regulations. Independent ISPs — facing an existential threat — sued, and the case went all the way to the Supreme Court.

The Supreme Court ruled that the law was ambiguous — you could make reasonable arguments on both sides. And under Chevron, that meant the FCC got to decide the best way to interpret the law.

The ruling was an earthquake for the broadband industry. The FCC took it as a green light to deregulate telephone companies’ broadband services as well. That effectively put independent ISPs out of business, leaving us with today’s broadband duopoly. And it created a lot of uncertainty about how the broadband industry would be regulated.

Under Chevron, the Supreme Court said that the FCC is allowed to deregulate broadband, but it didn’t say it was required to do so. So under President Barack Obama, the FCC changed positions and declared that broadband is a telecommunications service — a declaration that allowed it to establish strong network neutrality protections. The courts upheld this decision under the Chevron principle. Now, Donald Trump’s FCC is likely to use that same discretion to dismantle Obama’s rules.

By deferring to the FCC, the Supreme Court created uncertainty about how broadband services would be regulated — uncertainty that has lingered to this day. Unless Congress steps in and changes the law, we’re now likely to see a big change in policy every time the White House changes hands.

Gorsuch is a Chevron skeptic

In 2016, Gorsuch was part of a three-judge panel that considered the case of an immigrant who was facing two seemingly contradictory rules. One allowed an unauthorized immigrant to petition the attorney general to adjust his legal status immediately, while the other required a 10-year wait outside the United States before he would be allowed to seek permission to enter legally. Going by a 2005 court ruling that held the first rule took precedence, Hugo Gutierrez-Brizuela filed the necessary paperwork and entered the United States.

But the Board of Immigration Appeals decided to read the law differently, holding that the 10-year waiting requirement did apply to Gutierrez-Brizuela. By the time the case had worked its way through the courts, seven years had passed. If Gutierrez-Brizuela had known the 10-year waiting period applied and had stayed outside the US, his waiting period would have been almost finished by this point. But instead, he could have been forced to leave the country and stay abroad for an additional 10 years.

In a scathing 2016 opinion, Gorsuch and his colleagues rejected this result as unfair and absurd. Gorsuch urged the Supreme Court to reconsider the entire concept of Chevron deference. The Supreme Court’s precedents in Chevron and the broadband case, he wrote, “permit executive bureaucracies to swallow huge amounts of core judicial and legislative power and concentrate federal power in a way that seems more than a little difficult to square with the Constitution of the framers’ design.”

If Gorsuch’s nomination is confirmed by the Senate, he could find that there are some fellow Chevron skeptics among his new colleagues. “Leading the charge is Justice Clarence Thomas, who last year questioned Chevron’s constitutionality,” writes Notre Dame legal scholar Jeffrey Pojanowski. “But he is no lone voice in the wilderness. Chief Justice Roberts voiced discomfort with the judicial abnegation to an ever-growing administrative apparatus.”

The court’s other conservatives have also shown some signs of skepticism, he writes, and there have even been signs that Justice Stephen Breyer thinks Chevron goes too far.

Chevron doesn’t reliably help the left or right

This might make it seem like overturning Chevron was a conservative cause. And in recent years, that’s often how things have broken down.

“If you took a snapshot before the 2016 election, you would see that most of the pro-regulatory groups probably liked Chevron, and anti-regulatory groups were against Chevron,” says Daniel Deacon, a legal scholar at the University of California Irvine.

But Deacon says that’s largely because there’s been a Democrat in the White House. If you look further back, it’s easy to find cases where the Chevron rule helped advance conservative goals.

In the Supreme Court’s 2005 broadband ruling, for example, Chevron deference allowed the Bush administration to deregulate the broadband market. Stricter judicial review would have led to a more “liberal” result of strictly regulating big cable and telephone companies.

Indeed, the same point applies to the Chevron case itself. In that 1984 case, the Reagan Environmental Protection Agency wanted to interpret Clean Air Act in a way that would have allowed Chevron to emit more pollutants. The National Resource Defense Council sued, arguing that the Clean Air Act required a stricter interpretation. But the Supreme Court sided with the Reagan administration, holding that the courts shouldn’t second-guess the EPA’s reading of the law if that reading was reasonable.

In a landmark 2007 case, in contrast, the Supreme Court ruled that the EPA was not entitled to Chevron deference in deciding whether to treat carbon dioxide as a pollutant. Here, the decision not to apply Chevron led to stricter environmental regulation.

So Chevron doesn’t reliably push the law to the right or the left. Rather, it magnifies the power of whoever is in the White House.

“Whether environmentalists or pro-business folks like Chevron deference tends to turn on who's the president,” Pojanowski told me. “Chevron allowed Reagan to deregulate, whereas Chevron allowed the Obama administration to do a lot more. These statutes were passed in the 1970s and haven't been updated in a while.”

Whether you think that’s good or bad may depend on how worried you are about the increasing dysfunction in Congress. In an ideal world, legal ambiguities — like whether to regulate broadband services as common carriers or whether carbon dioxide should be regulated as a pollutant — would be resolved by Congress passing new legislation.

But with the political system increasingly polarized, Congress legislates less and less often — especially about arcane details of administrative law. As a result, agencies are often forced to interpret laws that haven’t been updated in decades. And sometimes, that means continuing to apply legal categories long after technological or scientific developments (like the invention of the internet or emerging science of climate change) makes those categories a poor fit for the real world.

Chevron deference gives agencies greater flexibility to adapt an old law to changing circumstances. But Gorsuch worries that too much deference to regulatory agencies can make the regulatory process arbitrary and undemocratic. The Founders wanted Congress, not the executive branch, to make the laws, he believes, and Chevron deference flies in the face of that principle.