Jurisdiction (area)

A jurisdiction is the legal authority of a court, government, or other entity to make and enforce laws within a defined area.
Each state in a federation—such as Australia, Germany, and the United States—forms a separate jurisdiction. Certain laws, however, may be uniform across the constituent states and enforced by federal courts, resulting in a single jurisdiction for those purposes.
A jurisdiction may also prosecute individuals for crimes committed outside its territory if the perpetrator returns. Citizens from other jurisdictions can sometimes be extradited to a jurisdiction where the act is illegal, even if it occurred elsewhere.
Unitary states usually constitute a single jurisdiction. Notable exceptions include the United Kingdom, which has three separate legal systems: England and Wales, Scotland, and Northern Ireland. China also has separate jurisdictions for Hong Kong and Macao.