The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.
Later indications were that the Court may have been looking for ways to back off from Garcia. One device was to apply a
clear statement rule requiring unambiguous statement of congressional intent to displace state authority. After noting the serious constitutional issues that would be raised by interpreting the Age Discrimination in Employment Act to apply to appointed state judges, the Court in Gregory v. Ashcroft 1 explained that, because Garcia
constrained consideration of
the limits that the state-federal balance places on Congress’s powers, a plain statement rule was all the more necessary.
[I]nasmuch as this Court in Garcia has left primarily to the political process the protection of the States against intrusive exercises of Congress’s Commerce Clause powers, we must be absolutely certain that Congress intended such an exercise. 2
The Court’s 1992 decision in New York v. United States 3 may portend a more direct retreat from Garcia. The holding in New York, that Congress may not
commandeer state regulatory processes by ordering states to enact or administer a federal regulatory program, applied a limitation on congressional power previously recognized in dictum 4 and in no way inconsistent with the holding in Garcia. Language in the opinion, however, seems more reminiscent of National League of Cities than of Garcia. First, the Court’s opinion by Justice O’Connor declares that it makes no difference whether federalism constraints derive from limitations inherent in the Tenth Amendment, or instead from the absence of power delegated to Congress under Article I;
the Tenth Amendment thus directs us to determine . . . whether an incident of state sovereignty is protected by a limitation on an Article I power. 5 Second, the Court, without reference to Garcia, thoroughly repudiated Garcia’s
structural approach requiring states to look primarily to the political processes for protection. In rejecting arguments that New York’s sovereignty could not have been infringed because its representatives had participated in developing the compromise legislation and had consented to its enactment, the Court declared that
[t]he Constitution does not protect the sovereignty of States for the benefit of the States or State governments, [but instead] for the protection of individuals. Consequently,
State officials cannot consent to the enlargement of the powers of Congress beyond those enumerated in the Constitution. 6 The stage appears to be set, therefore, for some relaxation of Garcia’s obstacles to federalism-based challenges to legislation enacted pursuant to the commerce power.
Extending the principle applied in New York, the Court in Printz v. United States 7 held that Congress may not
circumvent the prohibition on commandeering a state’s regulatory processes
by conscripting the State’s officers directly. 8 Printz struck down interim provisions of the Brady Handgun Violence Protection Act that required state and local law enforcement officers to conduct background checks on prospective handgun purchasers.
The Federal Government may neither issue directives requiring the States to address particular problems, nor command the States’ officers . . . to administer or enforce a federal regulatory program. It matters not whether policymaking is involved, and no case-by-case weighing of the burdens or benefits is necessary; such commands are fundamentally incompatible with our constitutional system of dual sovereignty. 9
In Reno v. Condon, 10 the Court distinguished New York and Printz in upholding the Driver’s Privacy Protection Act of 1994 (DPPA), a federal law that restricts the disclosure and resale of personal information contained in the records of state motor vehicles departments. The Court returned to a principle articulated in South Carolina v. Baker that distinguishes between laws that improperly seek to control the manner in which states regulate private parties, and those that merely regulate state activities directly. 11 Here, the Court found that the DPPA
does not require the States in their sovereign capacities to regulate their own citizens, but rather
regulates the States as the owners of databases. 12 The Court saw no need to decide whether a federal law may regulate the states exclusively, because the DPPA is a law of general applicability that regulates private resellers of information as well as states. 13
The Court's most recent consideration of the anti-commandeering principle occurred in 2018 in Murphy v. NCAA.  14 In Murphy, Justice Alito, writing on behalf of the Court, invalidated on anti-commandeering grounds a provision in the Professional and Amateur Sports Protection Act (PASPA) that prohibited states from authorizing sports gambling schemes.  15 Noting the rule from New York and
In holding that Congress cannot command a state legislature to refrain from enacting a law, the Murphy Court reconciled its holding with two related doctrines.  20 First, the Court noted that while cases like Garcia, Baker, and Condon establish that the anti-commandeering doctrine "does not apply when Congress evenhandedly regulates activity in which both States and private actors engage,"  21 PASPA's anti-authorization provision was, in contrast, solely directed at the activities of state legislatures.  22 Second, the Court rejected the argument that PASPA constituted a "valid preemption provision" under the Supremacy Clause.  23 While acknowledging that the "language used by Congress and this Court" with respect to preemption is sometimes imprecise,  24 Justice Alito viewed "every form of preemption" to be based on a federal law that regulates the conduct of private actors—either by directly regulating private entities or by conferring a federal right to be free from state regulation.  25 In contrast, PASPA's anti-authorization provision did not "confer any federal rights on private actors interested in conducting sports gambling operations" or "impose any federal restrictions on private actors."  26 As a result, the Murphy Court viewed the challenged provision to be a direct command to the states in violation of the anti-commandeering rule.  27