Celebrating Tetra Tech EC, Inc. v. DOR

Today marks one year since the Wisconsin Supreme Court officially eliminated all levels of deference to agency interpretation of law in Tetra Tech EC, Inc v. DOR (Tetra Tech). As we celebrate the anniversary, it is worth remembering why the decision made a difference.

Judicial deference to agency interpretation of law occurs when a judge submits to an administrative agency’s reading of a statute simply because the agency is an agency. In other words, even if the court thinks a better reading of the statute exists, it still must accept the agency’s interpretation. Variations of judicial deference occur at all levels of federal and state courts, the most famous being federal Chevron deference.

Prior to Tetra Tech, the Wisconsin Supreme Court gave three levels of deference—great weight, due weight, and de novo (or, no deference.) Depending which level the agency qualified for, the court would either submit to the agency’s interpretation under all circumstances, submit if the court found an equal but not better reading of the statute, or give no deference.

With Tetra Tech, the court eliminated the first two levels of deference leaving only the de novo standard, or no deference. See GLLF’s analysis. It did so because it found judicial deference to agency interpretation of law violated two constitutional principles: separation of powers and due process.

Separation of powers represents a familiar argument against judicial deference. The doctrine holds that each branch of government has certain, core powers that it cannot share. For the court, this means the power to say “what the law is.” Thus, by automatically accepting an agency’s interpretation of law, a court allows the agency to say “what the law is” and violates the separation of powers.

Due process provided a more novel argument and one only briefed by GLLF. Under due process, judicial deference to agency interpretation of law represents a fairness issue. The judge’s role is that of neutral arbitrator. But when a litigant takes an agency to court, judicial deference means the judge automatically sides with one of the parties. It violates the due process rights of the non-agency party and creates a fairness problem in the courtroom.

Tetra Tech was a landmark decision, both in Wisconsin and out. It returned authority to the court where it belongs and placed litigants back on equal footing with agencies on interpretations of law before the court. And that makes it a decision worth celebrating for many years to come.