Anthony Kennedy

“ It is correct in one sense to say that if the National Government has the power to act under the Necessary and Proper Clause then that power is not one reserved to the States. But the precepts of federalism embodied in the Constitution inform which powers are properly exercised by the National Government in the first place. ”

“ The opinion of the Court should not be interpreted to hold that the only, or even the principal, constraints on the exercise of congressional power are the Constitution's express prohibitions. The Court's discussion of the Tenth Amendment invites the inference that restrictions flowing from the federal system are of no import when defining the limits of the National Government's power, as it proceeds by first asking whether the power is within the National Government's reach, and if so it discards federalism concerns entirely. ”

“ Federal prisoners often lack a single home State to take charge of them due to their lengthy prison stays, so it is incumbent on the National Government to act. This obligation, parallel in some respects to duties defined in tort law, is not to put in motion a particular force (here an unstable and dangerous person) that endangers others. Having acted within its constitutional authority to detain the person, the National Government can acknowledge a duty to ensure that an abrupt end to the detention does not prejudice the States and their citizens. ”