In an 8-0 decision on Thursday, June 7, the Mississippi Supreme Court announced that it will no longer give any deference to state agencies’ interpretations of their governing statutes. This marks a sharp departure from the traditional deference the courts had shown to agencies, although as the decision correctly states, that deference had been eroding in recent years.

The decision in King v. Miss. Military Department ultimately affirmed the ruling for the agency, but made it clear that the Court sees the judicial branch as the sole authority under the Mississippi Constitution when it comes to interpreting statutory law:

Pursuant to the foregoing reasoning, we announce today that we abandon the old standard of review giving deference to agency interpretations of statutes. Our pronouncements describing the level of deference were vague and contradictory, such that the deference could be anywhere on a spectrum from “great” to illusory.  Moreover, in deciding no longer to give deference to agency interpretations, we step fully into the role the Constitution of 1890 provides for the courts and the courts alone, to interpret statutes.

The decision does not affect deference to federal agencies, which remains governed by the “Chevron” standard. Nor does the decision directly address whether state agencies’ interpretations of their own regulations will merit deference. But the courts will no longer accept on faith that an ambiguous or unclear statute means what the state agency says it means.

Anyone with an administrative-agency case pending, before the agency itself or in the courts, or contemplating a challenge to agency action, may be affected by this decision. Note that the decision is not yet final and could be subject to a motion for rehearing, though it would be surprising if an 8-0 decision were reversed on rehearing.