Whether the USDA's categorical requirement that dangerous animals be enclosed by an eight-foot perimeter fence was an interpretive rule exempt from APA notice-and-comment procedures.
Holding
No. The eight-foot fence requirement was a legislative rule, not a valid interpretive rule, and was invalid because the Department adopted it without notice and comment.
Reasoning
The APA generally requires an agency to give public notice of a proposed rule, accept written comments, and publish the rule's basis and purpose. Interpretive rules are exempt because they merely announce an agency's understanding of a preexisting statute or regulation, rather than create new binding obligations.
The Animal Welfare Act authorizes the Secretary to formulate minimum standards for animal handling and housing. A binding standard created under that delegation is ordinarily legislative: Congress gave the agency authority to choose and impose the duty, rather than supplied a specific duty for the agency simply to interpret. Thus, the Department could avoid notice and comment only by showing that the eight-foot requirement genuinely interpreted its existing structural-strength regulation.
Even assuming the structural-strength regulation embodied a general duty of secure containment, an eight-foot perimeter-fence mandate could not be derived from that generality through interpretation. The regulation speaks of materials, structural soundness, repair, protection, and containment; it says nothing about perimeter fences, their height, or a required distance from animal pens.
The choice of eight feet was an arbitrary policy choice in the relevant sense: it was a selection among plausible means of implementing secure containment, not a conclusion compelled by the regulation's meaning. Nothing in ordinary legal reasoning establishes why the proper minimum is eight feet rather than seven and a half, nine, or ten feet, or why the fence must be three feet from a pen. Such choices are legislative judgments requiring the participatory safeguards of notice-and-comment rulemaking.
The court did not hold that numerical rules can never be interpretive. In technical fields, a number may reflect established criteria, and an agency may also use a rebuttable numerical presumption tied to an underlying standard. But the Department's directive was a flat, unbending command rather than a rebuttable application of secure containment to particular circumstances. Its practical impact on many animal dealers, who might have to replace existing fences at substantial expense, reinforced the need for public participation before the rule became binding.