Equidistance principle

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The equidistance principle or principle of equidistance, in maritime boundary claims, is a legal concept that a nation's maritime boundaries should conform to a median line that is equidistant from the shores of neighboring nations. The concept was developed in the process of settling disputes in which the borders of adjacent nations were located on a contiguous continental shelf:

Maritime boundary boundary between marine zones over which countries have rights, or between such zones and international waters

A maritime boundary is a conceptual division of the Earth's water surface areas using physiographic or geopolitical criteria. As such, it usually bounds areas of exclusive national rights over mineral and biological resources, encompassing maritime features, limits and zones. Generally, a maritime boundary is delineated at a particular distance from a jurisdiction's coastline. Although in some countries the term maritime boundary represents borders of a maritime nation that are recognized by the United Nations Convention on the Law of the Sea, maritime borders usually serve to identify the edge of international waters.

Equidistant point that is at the same distance to every object in a given set

A point is said to be equidistant from a set of objects if the distances between that point and each object in the set are equal.


An equidistance line is one for which every point on the line is equidistant from the nearest points on the baselines being used. The equidistance principle is a methodology that has been endorsed by the UNCLOS treaty, but predates the treaty and has been used by the Supreme Court of the United States, states, and nations to equitably establish boundaries. [1]

United Nations Convention on the Law of the Sea International maritime law

The United Nations Convention on the Law of the Sea (UNCLOS), also called the Law of the Sea Convention or the Law of the Sea treaty, is the international agreement that resulted from the third United Nations Conference on the Law of the Sea, which took place between 1973 and 1982. The Law of the Sea Convention defines the rights and responsibilities of nations with respect to their use of the world's oceans, establishing guidelines for businesses, the environment, and the management of marine natural resources. The Convention, concluded in 1982, replaced four 1958 treaties. UNCLOS came into force in 1994, a year after Guyana became the 60th nation to ratify the treaty. As of June 2016, 167 countries and the European Union have joined in the Convention. It is uncertain as to what extent the Convention codifies customary international law.

The principle of equidistance represents one aspect of customary international law, but its importance is evaluated in light of other factors [2] such as history:

"Historic rights" or titles of some or another kind will acquire enhanced, rather than diminished, importance as a result of the narrowing of the 'physical' rather than the 'legal' sources of right. It is important to remember that, although historical claims were not successful in the Gulf of Maine case, the identification of a 'status quo' or 'modus vivendi' line in Tunisia–Libya was of decisive importance in confirming the equitableness of the first stage of delimitation. States will scrupulously avoid, more than ever, any appearance of acquiescence where acquiescence is not intended; prudent coordination can be expected between petroleum and mining ministries and the legal advisers of foreign ministries." Highet, Keith. (1989). "Whatever became of natural prolongation."

Status quo is a Latin phrase meaning the existing state of affairs, particularly with regard to social or political issues. In the sociological sense, it generally applies to maintain or change existing social structure and values. With regard to policy debate, the status quo refers to how conditions are at the time and how the affirmative team can solve these conditions for example "The countries are now trying to maintain a status quo with regards to their nuclear arsenal which will help them if the situation gets any worse."

Modus vivendi is a Latin phrase that means "mode of living" or “way of life”. It often is used to mean an arrangement or agreement that allows conflicting parties to coexist in peace. In science it is used to describe lifestyles.


The United States used equidistance in the 1805 Act of Congress that divided public lands by measurements as close as possible to "equidistant from those two corners which stand on the same line." One of the most notable historical events regarding equidistance is the Argument between Germany, Netherlands and Denmark. All three countries laid claim to a specific area within the ocean. Germany claimed that due to special circumstances they owned that land so the three countries fought through the united Nations. Eventually the ICJ stepped in and held a trial regarding the topic.

United States Federal republic in North America

The United States of America (USA), commonly known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, and various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is slightly smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U.S. is the third most populous country. The capital is Washington, D.C., and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico. The State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The extremely diverse geography, climate, and wildlife of the United States make it one of the world's 17 megadiverse countries.

International law also refers to equidistance. For example, Article 6 of the 1958 Geneva Convention on the Continental Shelf explains:

"Where the same continental shelf is adjacent to the territories of two or more States whose coasts are opposite each other, the boundary of the continental shelf appertaining to such States shall be determined by agreement between them. In the absence of agreement, and unless another boundary line is justified by special circumstances, the boundary is the median line, every point of which is equidistant from the nearest points of the baselines from which the breadth of the territorial sea of each State is measured." [1]

See also

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