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Last week, the Supreme Court heard nearly four hours of argument about the Chevron doctrine—including whether it should be cast aside. Not surprisingly, much of the argument consisted of different conceptions of what Chevron means. The nub of the problem is to specify what must happen for a court to depart from ordinary statutory interpretation (Chevron's step one) and defer to a reasonable agency interpretation of the statute (Chevron's step two). The argument (in Loper Bright Enterprises, Inc. v. Raimondo and Relentless, Inc. v. Department of Commerce) largely proceeded on the assumption that a court must turn to step two if it concludes the statute is "ambiguous" or includes a "gap." At some points, however, the advocates and the Justices thought that the critical question was whether Congress has implicitly "delegated" interpretive authority to the agency.
If we attempt to solve the problem by parsing what was said in the 1984 Chevron case, we quickly encounter the difficulty that Justice Stevens said both things. He wrote, on the one hand, that the court should employ "traditional tools of statutory construction" to determine whether a statute is "silent or ambiguous with respect to the specific issue." In other words, ambiguity is the key.
But, on the other hand, he also wrote that if Congress makes "an express delegation of authority to the agency to elucidate a specific provision of the statute by regulation," the agency's interpretation will prevail unless it is "arbitrary, capricious, or manifestly contrary to the statute." He immediately added: "Sometimes the legislative delegation to an agency on a particular question is implicit rather than explicit," in which case also the court should accept "a reasonable interpretation made by the administrator of an agency." In other words, explicit or implicit delegation to the agency to interpret is the key.
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