Pirate ships were painted gray for a reason. They blended into the shadowy area of the ocean along the horizon, where an inky sea met a smoky sky, a hint of a threat that the crew of every cargo ship must constantly be aware of but could never fully prepare for.

Gray areas remain dangerous places to navigate today. And we are sailing right into one after the Supreme Court announced its decisions in the companion cases of Loper Bright v. Raimondo and Relentless v. Department of Commerce on Friday morning.

In these cases, argued back in January, a group of fishing companies challenged the authority of the National Marine Fisheries Service to require vessel operators to pay for on-board observers who gather critical data needed for an agency to determine compliance with the federal fishery management plans. Save the Sound filed an amicus (or “friend of the court”) brief arguing the statute and its monitoring requirements are key to protecting healthy fish populations both for the environment and the future commercial fishing industry.

But the implications of this case extend far beyond catch limits and the cost of doing business. It’s not hyperbole to suggest that this decision could upend the entire framework that governs how federal agencies oversee and regulate any industry. Protections for everything from air quality to workplace safety (and of course fisheries) now hang in the balance.

What’s really on trial here is a 40-year-old legal doctrine known as “Chevron deference,” which basically has required that federal courts defer to administrative agencies’ reasonable interpretations when the intent of a statute is ambiguous. In other words, when a dispute enters a gray area, the agency — presumably staffed with subject matter experts whose judgment is best suited for navigating the tricky waters of nuance — retains authority.

While this sounds theoretical and technical, handcuffing agencies will directly impact your environment and quality of life. We’re seeing this play out right now in our efforts to protect Long Island Sound’s river herring. Around 200,000 or 300,000 of them bound for rivers in Connecticut and New York are being scooped up every year by massive midwater trawlers targeting mackerel and Atlantic herring. The New England Fishery Management Council is considering the best options for protecting this keystone species, listening to input from all stakeholders. Data provided by paid on-board observers is one critical piece to seeing the full picture of the problem. The experienced members of the Council — supplied with current and reliable bycatch data — would seem to be the appropriate people to determine what’s best for river herring when there are ambiguities. Should the fate of these fish come down to whichever judge happens to be assigned to a case?

Overturning Chevron is the latest in a series of recent Supreme Court decisions making it more difficult for agencies to act. Performing the job of a judge requires a generalist expertise in the law, not in the intricacies of, say, the geological and ecological differences among two dozen types of wetlands. Despite this, in last year’s Sackett v. Environmental Protection Agency, SCOTUS overrode the EPA’s longstanding interpretation that had survived more than 40 years through Democrat and Republican administrations and eliminated protections for many wetlands under the Clean Water Act. In West Virginia v. EPA, SCOTUS rejected EPA’s determination of the “best system of emission reduction” to address climate change under the Clean Air Act because it did not protect dirtier industries such as coal-fired power plants.

Now that the Chevron deference has been dumped, agencies will have an increasingly uphill battle to effectively regulate industry and protect the public. Any policy decision could wind up in court before one or more of the 1,500 federal judges who are often in conflict not just with the agency but with each other. Even the black and white cases could be argued as gray. In the end, the rules will no longer be shaped by science but by politics.

Justice Roberts had famously stated that the job of judges “is to call balls and strikes, and not to pitch or bat.” But his decision in these cases moves judges from behind the plate (deciding whether an agency interpretation was reasonable) and puts a bat in their hands (so they can determine policy themselves).

We are entering an area of endless gray, and the Loper Bright and Relentless decisions have determined that the policy preferences of individual judges, rather than science and expertise, will be our guides. With these federal protections diminished, it will be more important than ever to continue and increase our efforts at the state and regional level to protect Long Island Sound, clean air and open space.

Roger Reynolds is the senior legal director for Save the Sound, an environmental organization.