Admiralty and maritime jurisdiction is part of the judicial power conferred upon the courts of the United States by the Constitution.  Subject to specific statutes, the authority of a district court is generally limited to the geographical limits of the district, including the territorial waters bordering the district.  However, bodies of water that are wholly located within a single state and are not navigable nor used in interstate or foreign commerce would not be included in the admiralty jurisdiction.

There are three types of maritime actions such as:

• in rem,
• quasi in rem and
• in personam.

In rem actions are brought to enforce any maritime lien, which is a right against a particular vessel involved directly in the incident.  The action could have stemmed from a ship mortgage, repairs, the supplying of necessaries, crew wages, collision liability, loss of or damage to cargo, bodily injury, salvage, wrongful death, or in accordance with authority granted under an applicable statute including some types of forfeiture actions.  In admiralty cases, to acquire jurisdiction in an in rem action, “Execution of a Warrant of Arrest” of the vessel or cargo is necessary.  Pursuant to Supplemental Rule C(2)(c) and E(3)(a), an in rem suit in an admiralty action must be started in the district where the vessel or cargo or tangible property is located.  If the vessel or cargo or tangible property cannot be found or located therein, then the complaint may be filed in any district of the United States and the allegation made that it is expected within the district within the pendency of the action.  However, the court will not acquire admiralty jurisdiction until the vessel or cargo or tangible property is actually arrested within that district or dependent on the facts, the parties otherwise agree to jurisdiction.

In personam actions are proceedings against a person or persons such as the owner or owners of a vessel.  An action in personam is used to secure a judgment against the person rather than against the vessel or other property involved in the incident.  Generally, an action will be brought both in personam and in rem.