Puerto Rico laws are based on a legal system that operates within a self-governing territory of the United States that is formally known as “The Commonwealth of Puerto Rico”.  It operates within the U.S. constitutional system and has a mixed legal system. The head of state is the President of the United States of America, and the head of the “Commonwealth” is an elected governor.

Like other States of the Union, Puerto Rico has its own constitution and has authority over its strictly internal affairs.US federal laws apply in Puerto Rico unless expressly excluded by particular legislation.

Federal government has jurisdiction over areas such as: interstate trade; treaties, foreign relations and commerce; customs administration; control of air, land and sea, including maritime laws; immigration; nationality and citizenship; currency; defense and military matters; the U.S. constitutionality of laws; federal jurisdiction and procedures; telecommunications; agriculture; mining and minerals; highways; the postal system; social security; and other areas generally controlled by the federal government.  There is a separate US federal court system.

The only representation the government (and people) of Puerto Rico has before Congress is one nonvoting representative, called the Resident Commissioner to the U.S. House of Representatives.

Puerto Rico parallels the same separation of power structure of the U.S. Constitution and thus, its government consists of an executive, legislative and judicial branch.  The judicial branch consists of a Supreme Court, a Circuit Court of Appeals and a First Instance Court. The Supreme Court of Puerto Rico is the  highest state court and the court of last resort in Puerto Rico. Decisions  are reviewable only by the Supreme Court of the United States by certiorari when an important question of federal law is involved. The justices  are appointed by the Governor of Puerto Rico and confirmed by majority vote by the Senate.  The Courts of Puerto Rico has concurrent jurisdiction with federal courts to interpret federal laws, unless the Supremacy Clause requires otherwise.

The United States District Court for the District of Puerto Rico  is a federal court created under the Constitution of the United States and part of the U.S. Courts.  It is the federal trial court for the judicial district of Puerto Rico with  six active Article III judges, several senior judges, and four Magistrate Judges.   It has jurisdiction to hear nearly all categories of federal cases, including both civil and criminal matters.  The United States Court of Appeals for the First Circuit hears appeals from the district court.  The First Circuit includes the Districts of Maine, Massachusetts, New Hampshire, Puerto Rico and Rhode Island.