The court also agreed with the CJO's decision that migratory birds would suffice as the connection between the wetlands and interstate commerce. Though the activity may be local in nature, if it exerts some substantial impact on interstate commerce, Congress has the power to regulate direct or indirect effects. The Seventh Circuit held the potential visitation of migratory birds would suffice to put those wetlands within the power of Congress. These people travelling from other states to hunt or observe would generate interstate commerce and, with this indirect effect on commerce, the CWA regulations can reach the wetlands under the interstate commerce clause. Thus, the Seventh Circuit court followed the construction that a wetland would fall under the CWA if the degradation or deconstruction could potentially affect interstate commerce.
Migratory birds visiting the wetland are sufficient to show such a minimal effect.
Though the Seventh Circuit agreed on the definition of which navigable waters would fall under the CWA, the court did not find the EPA provided sufficient evidence to prove Area A fell under that definition of navigable waters. On review, the court must find such relevant evidence as a reasonable person might accept as adequate to support a conclusion. The ALJ did not find any evidence that migratory birds visited Area A after a twenty-one day hearing on the issue. However, the CJO concluded on the same evidence that Area A was suitable for migratory birds. Furthermore, another witness testified Area A had only a moderate suitability for migratory birds.