Right. Chevron was about letting agencies help interpret ambiguous statutes that delegate authority from Congress to an agency. But by definition, Congress can

Right. Chevron was about letting agencies help interpret ambiguous statutes that delegate authority from Congress to an agency. But by definition, Congress can't delegate authority it doesn't have. In particular, Congress doesn't have the authority to transgress the Constitution. So there's no question of whether the statute permits the agency to transgress the Constitution. It never does and never can. Even if the law said "Congress authorizes the CBP to violate the Constitutition," the agency would still not be authorized to violate the Constitution.