On August 9, a lawsuit was filed in Connecticut that aims to stop all legal cannabis activity in the state and declare the state’s 2021 legalization framework as unconstitutional. The complaint, filed by a local homeowners advocacy group against the Zoning Board of the City of Stamford and the Stamford Mayor, alleges that Connecticut’s legalization framework, the Responsible and Equitable Regulation of Adult-Use Cannabis Act (RERACA), violates both the state and federal constitutions by legalizing federally prohibited conduct, and is therefore preempted under both. In addition, the complaint alleges that the state’s social equity council violates the Connecticut constitution by providing exclusive public emoluments or privileges to certain groups based on race, and that the approval by certain board members of changes in zoning regulations was invalid due to several board members terms having previously expired.
This article will focus on the plaintiff’s preemption claims under federal law and discuss the general framework and limitations under which preemption is analyzed by federal courts. We will also discuss several federal cases where the preemption doctrine was applied to state cannabis schemes, and how the courts interpreted and applied the doctrines.
The Supremacy Clause of the U.S. Constitution states that state and local governments are prohibited from enacting laws that conflict with federal law. In such cases, the Supremacy Clause generally voids the state law under the theory of federal preemption. When applying the preemption doctrines, courts will typically apply three limiting principles as a check on federal overreach: (1) a determination of congressional intent, which informs the intended scope of preemption under the federal act; (2) the presumption against preemption, which applies where the legislation touches on areas involving the “historic police powers” of the states; and (3) the anti-commandeering rule, which states that the federal government may not “commandeer” state governments to “influence the manner in which states regulate private parties.”
Under federal law, there are two general categories of federal preemption: express and implied. In cases of express preemption, the federal law in question contains a specific provision delineating the scope to which state laws will be preempted by federal law. On the other hand, where a federal law does not contain an express preemption provision, courts may imply the preemptive effect of a statute by analyzing the purpose and structure of the federal law in question. Under implied preemption, a state law may be preempted by either field preemption (where federal law is so pervasive that Congress left no room for the states to supplement it) or by conflict preemption (where [a] it is physically impossible to comply with one law without violation of the other, or [b] where state law poses an obstacle to the enforcement of the federal law).
Preemption Under the CSA
In their complaint, the plaintiffs do not specifically state the theory under which they assert that the RERACA is preempted by the Controlled Substances Act (CSA) — they simply state that “[t]he State marijuana legalization scheme runs afoul of the CSA and is preempted thereby.” In drafting the CSA, lawmakers included an express preemption provision, which limits the CSA’s preemptive affect to instances where “a positive conflict [exists] between that provision of this subchapter and that State law so that the two cannot consistently stand together.”  In many cases, courts have held that this provision limits the type of preemption under the CSA to conflict preemption, as the provision itself expressly declines to assert field preemption.
Impossibility preemption has been applied narrowly by the Supreme Court — to apply, the conflicting state and federal law must “impose directly conflicting duties,” such that compliance with one law necessarily requires violation of the other. At this point in the analysis, the authorities are split — some courts have held that it is possible for individuals to comply with both state and federal cannabis laws by refraining from any cannabis-related conduct, while other courts have held that it would be impossible to engage in specific state-legal cannabis activity without violating the CSA. It remains to be seen which train of thought the Supreme Court would follow in an impossibility analysis regarding a state’s cannabis laws, and the outcome of the analysis would likely depend on the effect of the particular state law in question.
Obstacle preemption, on the other hand, is applied when a state law “stands as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress.” A court will look to the act as a whole, and to the congressional intent of the act, to determine whether the state law is a sufficient obstacle to warrant preemption. In the case of the CSA, the Supreme Court held that the primary objectives of the act were to minimize drug abuse in the U.S., and to regulate the trafficking of controlled substances, both legal and illegal.
Courts vary in the extent to which they apply the impossibility and obstacle preemption doctrines. Regardless of which framework a court chooses to employ (Supreme Court precedent suggests that a court should likely use both), courts have generally held that when a state cannabis law contains an affirmative authorization to violate federal law, that state law is preempted by the CSA. In addition, state laws that require someone to violate the CSA are also generally preempted. However, in several cases, a simple exemption from state criminal liability has not been found preempted by the CSA. These cases often cite the limiting principles discussed above, specifically the presumption against preemption in areas where the states have historic police powers, and the anti-commandeering rule against federal coercion. Even amongst these similarities, jurisdictions vary wildly in how they apply the conflict preemption doctrines, so these patterns should not be taken as hard-and-fast rules.
Why It Matters
The lawsuit challenging Connecticut’s cannabis legalization framework has brought the intricate doctrines of federal preemption to center stage. The application of these doctrines varies between jurisdictions, making a prediction of the court’s decision in this case difficult to predict. While the outcome remains uncertain, the challenge underscores the delicate balance between state and federal law in the ever-evolving cannabis landscape. As we await the verdict, it becomes evident that the quest for clarity in the legal cannabis industry is far from reaching its conclusion.
 Stamford Neighborhoods Coalition et al. v. Zoning Board of the City of Stamford et al., case number FST-CV23-6062611-S in the Superior Court, Stamford Judicial District (hereinafter “the Plaintiffs Complaint”), available at https://www.law360.com/articles/1709768/attachments/0; see also Steele, Lawsuit Vies To Shut Down Conn. Cannabis Industry, Law360 (Aug. 10, 2023), available at https://www.law360.com/articles/1709768.
 U.S. Const., art. VI, cl. 2.
 Wardair Canada, Inc. v. Florida Dept. of Revenue, 477 U.S. 1, 6 (1986).
 Rice v. Santa Fe Elevator Corp., 331 U.S. 218, 230 (1947).
 See New York v. U.S., 505 U.S. 144 (1992); see also Reno v. Condon, 528 U.S. 141, 150-51 (2000).
 Gade v. National Solid Wastes Management Ass’n, 505 U.S. 88, 98 (1992)
 The Plaintiffs Complaint at 6.
 21 U.S.C.A. § 903 (emphasis added)
 See e.g., Ter Beek v. City of Wyoming, 823 N.W.2d 864, n 5 (2012); see also Gonzales v. Oregon, 546 U.S. 243, 251 (2006)
 Barnett Bank of Marion County, N.A. v. Nelson, 517 U.S. 25, 31 (1996)
 See e.g., Emerald Steel Fabricators, Inc. v. Bureau of Labor and Industries, 348 Or. 159, 176 (2010)
 See e.g., Bourgoin v. Twin Rivers Paper Company, LLC, 187 A.3d 10, 19 (Me. 2018)
 Freightliner Corp. v. Myrick, 514 U.S. 280, 287 (1995)
 Crosby v. National Foreign Trade Council, 530 U.S. 363, 373 (2000)
 Gonzales v. Raich, 545 U.S. 1, 12 (2005)
 See e.g., Wyeth v. Levine, 555 U.S. 555 (2009)
 See e.g., Emerald Steele, 348 Or. 159 (Oregon’s affirmative authorization to use medical cannabis was found to be preempted under obstacle preemption);
 See e.g., Bourgoin, 187 A.3d 10 (a requirement for employers to reimburse employees for the cost of medicinal cannabis was found to be preempted under impossibility preemption).
 See e.g., Ter Beek, 823 N.W.2d 864 (immunity provision for medical patients was not preempted).