Is there or isn't there a “presumption against preemption”? The Supreme Court continues to mention it, but then does, or does not, apply it in a way that helps us understand what it is. This Article explores the Court's preemption opinions in the last several decades, particularly its most recent pronouncements, and concludes that, indeed, there is a presumption against preemption. It is a "new" presumption in the sense that it is born of the Court's active preemption docket in the last two decades, which has more narrowly defined both express and implied preemption analysis. The "new" presumption is stronger in express preemption cases, operating as a true default rule in the absence of clear and manifest congressional intent to preempt, but is less rigid, or, in other words, more forgiving in implied preemption cases, giving breathing room to the definition of actual conflict while maintaining focus on articulated congressional objectives.

The uncertain course of preemption doctrine in the last two decades has contributed to a substantial increase in preemption arguments being made that perhaps never should have been made. The Court opened the door to many of those arguments by its display of uncertainty over the place of the presumption against preemption. The Court may have closed that door by its recent preemption decisions that clarify the importance of the presumption against preemption in both express and implied preemption cases. This Article explains the "new" presumption against preemption that has resulted, and hopes to reduce the current uncertainty over the role of the presumption in preemption doctrine.

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Notes/Citation Information

Hastings Law Journal, Vol. 61, No. 5 (May 2010), pp. 1217-1255


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