Admiralty Law
Admiralty Law is synonymous with Maritime Law. Notwithstanding, Admiralty Law is more correctly understood as a subset of Maritime Law.
Admiralty Law evolved as the mixture of international common law and civil law or codes, decided by judges who would look to international practices and customs, as well as to the local civil law, to determine what standards to apply to maritime disputes.
Maritime Law
Maritime Law comprises not only Admiralty Law but also maritime statutes and regulations enacted on a nation-by-nation basis or based on international conventions.
Over time, countries have tended to enact specific statutes to codify traditional Admiralty Law concepts, such as maritime liens and cargo claims, or to address other maritime matters that were not traditionally viewed as admiralty issues, such as vessel mortgages and marine insurance.
Recently, most countries have implemented specific statutes regarding ship construction standards, pollution prevention regulations, seafarer protection regulations, and similar laws.
International Maritime Law
Much of the International Maritime Law is now based on international conventions developed under the auspices of the IMO (International Maritime Organization).
In UK, the local maritime courts were centralized by the English royal government and placed under the authority of the Lord High Admiral. That eventually led to tension between the admiralty courts and the common law courts over jurisdiction and the benefits of fees from the handling of disputes.
By the time of the American Revolution, the two court systems had reached a point of equilibrium, with the Admiralty Courts claiming jurisdiction over matters arising on tidewaters and the high seas, and the local courts assuming jurisdiction over all other disputes.
In the USA, Admiralty Law and Maritime Law split in jurisdiction was replicated when the Founding Fathers drafted the U.S. Constitution.
Common Law
While most Common Law disputes, such as torts, contract, and property issues, were left to the state common law courts, the Constitution expressly provided for federal jurisdiction over admiralty matters. Article III, Section 2, Clause 1 states that “The judicial power shall extend to all cases of admiralty and maritime jurisdiction”.
The federal admiralty jurisdiction was implemented through the Judiciary Acts of 1789 and subsequent versions, now codified in the US Code. The statute setting out the jurisdiction of federal district courts over maritime cases states: Admiralty, Maritime and Prize Cases.
Saving to Suitors in all Cases
The district courts shall have original jurisdiction, exclusive of the courts of the States, of any civil case of admiralty or maritime jurisdiction, Saving to Suitors in all cases all other remedies to which they are otherwise entitled.
As a result, Maritime Law is established as a matter of Federal Law, developed largely through judge-made common law.