Pardon us, but we just don’t understand the legal reasoning behind the Washington Supreme Court’s decision to give the state Department of Ecology a free pass.

With this pass in hand, the folks at Ecology can make up rules anytime they want, and exempt whoever they want, without any public comment or accountability. As long as the rule doesn’t apply to everyone, Ecology can do what it wants, shielded from public scrutiny.

The court’s ruling “says you can go beyond the laws and rules as long as you don’t make it uniformly applicable,” Washington Water Resources Association executive director John Stuhlmiller said. “To me that’s unconscionable. That’s not how you regulate.”

In the case the court decided, Ecology made an end run around the required process for writing a new rule to limit the amount of nitrogen a sewage plant can pump into Puget Sound.

For the record, limiting sewage discharge into the ocean is a good idea; it’s just how Ecology did it that smells.

The agency decided that only 29 of a total of 107 sewage plants along the shores of Puget Sound should limit discharges. The others were exempted and allowed to keep pumping.

By allowing some sewage plants to continue dumping into Puget Sound and stopping others, Ecology walked a legal tightrope, according to the Supreme Court. It had come up with a “requirement” and not a “rule,” Chief Justice Helen Whitener wrote for the majority, which overturned a trial judge and an appeals court.

The difference between a requirement and a rule lay in how the two are viewed. A rule would require Ecology to follow the state Administrative Procedure Act and undertake a public process, allowing comments and public hearings to give people and the sewage districts that will be impacted the opportunity to offer their opinions.

Such public processes help the public to understand what Ecology is doing and why. It also allows Ecology to correct any mistakes it made in the initial drafts of the rule. The public process makes a rule better.

On the other hand, a requirement allows Ecology to essentially do what it wants. It can pick and choose winners and losers in which sewage plants would have to undergo expensive modifications.

The stakes in this case were high — billions of dollars high. King County, which has four sewage plants that discharge nitrogen into Puget Sound, estimated it would be on the hook for $9 billion to $15 billion in modifications, forcing sewer rates to jump 23% to 40%.

It just seems like members of the public, who ultimately will pay those higher rates, ought to also have the opportunity to comment on Ecology’s new requirement.

Accountability is a bedrock principle of a democratic republic — except in Washington state.