What You Need to Know About International Law

The practice of international law can impinge on cases taken on and decisions made by the U.S. Supreme Court both in reference to legal controversies which span international borders and to the use of other law codes as sources for guidance and instruction. The relevance of international laws is generally accepted by professionals in and observers of the American field of law when it is in regard to the former category, but the practice has caused more controversy in the latter such cases.

Some American political and legal arguments contend that the sovereign authority of the country as a whole is imperiled by a reliance on foreign codes of law for any kind of authority. Despite this argument, the field of international law has in the past derived much of use from American Constitutional law, and with the expansion of comprehensive and functioning legal systems across the world, it is not unlikely that the Supreme Court will continue to deal with the proper relationship of international laws to the American judicial system.

Early Supreme Court rulings on the issue of international law often involved issues and disputes arising between the ships of different countries engaged in sea commerce. In cases of this kind and similar legal controversies, the Supreme Court would openly examine international laws and mention such codes as authorities in its opinion. A specific instance of international law occurring in the early period of the Supreme Court is a case involving questions over property included in the Louisiana Purchase from France and also held at a previous point by Spain.

To this end, the Justices studied French and Spanish real estate statutes before rendering a decision for the American litigant. Similar questions arose much later in reference to inter-North American commerce conducted as part of NAFTA and the recovery of property lost in Europe during World War II.

A more controversial appearance of international laws in Supreme Court theory has been the citation of other countries' law statutes in regard to the rights of Americans, which in turn have prompted complaints of American courts compromising American sovereignty. The international law controversy began toward the end of the 20th Century, when Justices began looking to legal codes for practices and rules that they considered more humane and fair than those currently observed in the United States. Legal and political commentators would sometimes notice this trend, to their chagrin or endorsement, when they saw the Justices' own citation of foreign and international law in the opinions they rendered.

Discussion of the use of international law by the Supreme Court came to new prominence when Justice Anthony Kennedy cited precedents from general European laws and English courts in the Lawrence v. Texas case disallowing the legal prohibition of same-sex intercourse. Kennedy would later cite international law to similar ends, and to similarly much-noted, often reviled effect, in appealing to the United Nations' Convention on the Rights of the Child against the practice of executing minors.

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