What is International Law?

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Definition of International Law

International law is a system of treaties and agreements between nations that governs how nations interact with other nations, citizens of other nations, and businesses of other nations. International law typically falls into two different categories. "Private international law" deals with controversies between private entities, such as people or corporations, which have a significant relationship to more than one nation. For example, lawsuits arising from the toxic gas leak in Bhopal, India from industrial plants owned by Union Carbide, a U.S. corporation would be considered a matter of private international law.

"Public international law" concerns the relationships between nations. These include standards of international behavior, the laws of the sea, economic law, diplomatic law, environmental law, human rights law, and humanitarian law. Some principles of public international law are written, or "codified" in a series of treaties, but others are not written down anywhere. These are known as "customary" laws, and nations consent to them by doing nothing.

Since most international law is governed by treaties, it's usually up to the individual nations to enforce the law. However, there are a few international organizations that enforce certain treaties. The most notable example is the United Nations, which has 192 member states.

Terms to Know

  • Ambassador: A government official who facilitates communication between two nations.
  • International Court of Justice: The judicial branch of the United Nations, which resolves disputes between nations and issues advisory opinions on issues of international law.
  • Interpol: An international network of police organizations that work together to solve international law.
  • Security Council: A special committee within the United Nations that determines whether a particular situation will create a threat to international security.

Practice Area Notes

Most people never have to interact with international law. Those that do interact with international law are part of a large corporation's legal team or victims of international human rights abuses seeking asylum in safer countries.

However, a basic knowledge of international law is still useful for the general public. Decisions regarding where and when to send U.S. armed forces are made in the shadow of international treaties, and differing safety regulations between nations affect many of the products in the U.S. marketplace.

Related Practice Areas

  • Business & Commercial Law: International law affects where products are manufactured, the ethical and safety standards of different processing plants, and trade regulations.
  • Environmental Law: International environmental laws become more important as more nations realize that the activities of one nation can impact the global environment.
  • Civil Rights: The U.S. grants its citizens many rights and freedoms that other nations do not provide to their citizens. Refugees from strict totalitarian regimes often try to come to the U.S. to escape dire situations in their own countries.
  • Admiralty & Maritime Law: The nations share access to the oceans in order to facilitate trade. Consequently, the field of admiralty law provides rules for how to interact with foreign vessels.

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