Maritime Jurisdiction of the Federal Government

In accordance with Article III of the United States Constitution, the federal government has jurisdiction over all admiralty and maritime cases. This means that the federal government has jurisdiction over all criminal offenses that are committed on the high seas, on any other waters within the jurisdiction of the United States, or on any vessel that belongs to the United States, to a United States citizen, or to a corporation, which vessel is located within the admiralty or maritime jurisdiction of the United States and not within the jurisdiction of a state.

The definition of the terms “high seas” has historically meant the open and unenclosed waters of the sea beginning at the low-water mark. The terms have also been used to describe waters that are beyond the marginal belt or beyond the “territorial seas.” A Presidential proclamation in 1988 extended the “territorial seas” of the United States from 3 to 12 nautical miles.

The fact that a state has fixed its boundary beyond the low-water mark and claims jurisdiction to the marginal seas does not mean that the federal government does not have maritime jurisdiction. A state may only exercise jurisdiction over the marginal portion of the seas as long as there is no conflict with federal law or with the laws of other countries. However, a state may enforce its laws upon its citizens and its vessels that are on the high seas and that are beyond the state’s territorial waters. If a state’s citizen or vessel violates both federal and state law, the federal government may defer prosecution of the citizen or the vessel to the state.

Although the federal government has maritime jurisdiction over criminal offenses that are committed by a United States citizen on a United States vessel on the high seas, the government does not have jurisdiction over offenses that are committed by foreign citizens on foreign vessels on the high seas. A vessel has the nationality of the country where it is registered and whose flag it is flying. The Convention on the High Seas, of which the United States is a party, gives the flag country of a vessel exclusive jurisdiction over the vessel when it is on the high seas. However, the federal government has jurisdiction over the vessel if the vessel is partially owned by a citizen of the United States.

The Great Lakes and their waterways are included with the maritime jurisdiction of the federal government if a vessel on the Great Lakes is a United States vessel. The federal government’s maritime jurisdiction may even attach to a foreign vessel on the Great Lakes unless the foreign vessel is within the harbor or waterways of a state.

The federal government has jurisdiction over certain offenses that are committed by a United States citizen or against a United States citizen on the high seas. These offenses include murder, manslaughter, maiming, kidnapping, rape, assault, and robbery.

The federal government also has jurisdiction over certain maritime offenses, even if the offenses occur within the jurisdiction of a state. Such offenses include a death that results from the criminal negligence of a ship’s officer or crew and a firing on a vessel.

Copyright 2012 LexisNexis, a division of Reed Elsevier Inc.