Federal preemption is the power of the federal government under the Supremacy Clause of the United States Constitution to displace a state law in favor of a federal law or regulation, when the state law conflicts with the federal law or regulation. Thus, when a conflict exists between a state law and a federal law or regulation, the federal law or regulation trumps, or preempts, the state law. Recently, defendants in personal injury lawsuits have employed federal preemption as a defense against plaintiffs’ tort suits brought in state court proceedings, in an effort to limit tort liability, as well as to diminish or escape a plaintiff’s recovery of punitive damages awards. This preemption defense is sometimes called constitutional tort reform, because it allows the U.S. Supreme Court to effectively reform state tort law through the application of constitutional limitations on state power in ways that limit a plaintiff’s right to recover in certain tort cases.