The Court distinguished its finding in Villamonte-Marquez from its most recent vehicle-stop precedent established in Delaware v. Prouse. In Prouse, the Court held that the fourth amendment prohibits police from stopping an automobile and detaining the driver to check his/her license and registration unless the officer has a reasonable suspicion of a law violation. In Villamonte-Marquez, the Court differentiated investigatory stops of vessels in waters offering ready access to the open sea from stops of automobiles on principal thoroughfares. First, the Court reasoned that permanent document checkpoints are not practical on waters where vessels can move in any direction at any time. Second, the Court indicated that documentation requirements applicable to vessels differ significantly from the system of auto licensing, and police officers patrolling highways can usually determine by observing a vehicle's license plate whether it is in compliance with State law; neither the Federal nor State Governments issue comparable license plates or stickers for vessels. Further, reasoned the Court, the statutes and regulations governing maritime documentation are more complex than the typical State requirements for vehicle licensing. The Court's decision is flawed in overstating the interests of the government in checking vessel documentation and in understating the privacy interests of vessel owners and operators. A total of 105 footnotes are provided.