"Plaintiffs challenge Arizona Revised Statutes § 13-2929, which attempts to criminalize the harboring and transporting of unauthorized aliens within the state of Arizona. The district court granted the plaintiffs’ motion for a preliminary injunction with respect to this provision on the basis that § 13-2929 is preempted by federal law. Arizona appealed. We conclude that the statute as written is void for vagueness under the Due Process Clause because one of its key elements—being “in violation of a criminal offense”—is unintelligible. We also find that the provision, however it is interpreted, is preempted by federal law and thus invalid under the Supremacy Clause. Therefore, we affirm the district court’s grant of a preliminary injunction." - Valle Del Sol v. Whiting, Oct. 8, 2013.