Congress gave the Attorney General the power to prevent a doctor from prescribing any federally listed medications, and the power over that list. In the ruling, Justice Kennedy wrote:
It would be anomalous for Congress to have so painstakingly described the attorney general's limited authority to deregister a single physician or schedule a single drug, but to have given him, just by implication, authority to declare an entire class of activity outside 'the course of professional practice' and therefore a criminal violation of the CSA. …The idea that Congress gave the attorney general such broad and unusual authority through an implicit delegation in the CSA's registration provision is not sustainable.Quoting a 2001 decision, Kennedy continued:
Congress, we have held, does not alter the fundamental details of a regulatory scheme in vague terms or ancillary provisions -- it does not, one might say, hide elephants in mouseholes.As Broder notes, there's another case in which the Administration is trying to argue that Congress granted them implicit authority despite the explicit prohibitions: the illegal wiretapping.
Sure, the law says that FISA and the criminal wiretapping statutes are "exclusive means by which electronic surveillance…may be conducted" (18 USC 2511). Sure, there are explicit ways to undertake warrantless wiretapping, and getting those warrants is dirt simple.
But the administration's extensive legal defense of the program essentially holds that either Congress has no power to regulate the practice of wiretaps on international phone liness, or vague terms and ancillary provisions in a Congressional resolution justify the program. The AUMF is the mousehole, a vast assault on the separation of powers is the elephant.
If Broder is right and on its face his argument has merit, this ruling was (among other things) a 6-3 shot across the bow on the illegal spying.
This would help explain why the conservatives on the Court ruled as they did, standing up for executive power rather than states' rights.