HISTORY OF THE MARITIME ZONES UNDER INTERNATIONAL LAW - FROM THE CANNON SHOT RULE TO UNCLOS *

For hundreds of years, the marine environment was free from regulation of fishing, shipping, and resource exploitation.  Over time, coastal States (countries) had an increased interest in national security and the enforcement of laws to protect its commerce and marine resources.  As a result, a balance was needed to maintain the freedom of navigation that many foreign maritime interests had relied upon.  This need for balance is captured in the history of the law of the sea.

The birth of a nation’s authority to control its coastal waters has been traced back to the sixteenth century.  In the seventeenth century, the father of international law and doctrine on the freedom of the seas, Grotius, recognized the existence of a nation’s jurisdiction over the coastal waters that could be effectively controlled from the land.  The extent to which a nation could control its coastal waters was largely based on the reach of its cannons on the shore.  Thus, the 3 nautical mile (nm) limit of the territorial sea resulted from what is often referred to as the “cannon shot” rule.  In the U.S., the creation of a territorial sea and contiguous zone date back to as early as the late 1700s in response to issues of national security and law enforcement at coastal areas, including a 1793 diplomatic note sent from Thomas Jefferson ** and legislation passed by Congress in 1799 to allow the boarding of foreign flag vessels within 12 nm from the coast. *** This zone was known as “customs waters” and was later called the “Contiguous Zone.”  By 1930 the proprietary rights of the coastal state over the resources of the territorial sea was well established, provided it did not interfere with a vessel’s right of innocent passage.  In 1945, President Truman issued a proclamation asserting rights to explore and exploit the oil and gas resources of the continental shelf outside of the 3 nm territorial sea.  In 1953, the U.S. Congress enacted legislation over the federal and state control of the continental shelf.  In 1958, international conventions were concluded in Geneva on the territorial sea, contiguous zone and continental shelf.  The concept of a fishery conservation zone was born in another Truman Proclamation but Congress did not enact laws regarding a 200 nm fishery conservation zone until 1976.  This evolved into a zone whereby a coastal nation had exclusive control over all economic exploration and exploitation of the natural resources off its coast.  By 1982, the custom of asserting a 12 nm territorial sea, 24 nm contiguous zone, and 200 nm EEZ was codified in the United Nations Convention on the Law of the Sea (UNCLOS).

* With permission from the National Oceanic and Atmopheric Administration's Office of Coast Survey website 4 September 2013 (http://www.nauticalcharts.noaa.gov/staff)/law_of_sea.html)

 ** Text of November 8, 1793 diplomatic note (sent by Secretary of State Thomas Jefferson to both Britain and France.)

 *** See ch.22, § 54, 1 Stat. 668 (1799)