Citizens who commit a crime in one state and then flee to another to escape prosecution must be returned to the original state.

The concept you're referring to is known as "extradition." In the United States, extradition between states is governed by the U.S. Constitution, specifically Article IV, Section 2, Clause 2, often called the Extradition Clause. It reads, "A person charged in any State with Treason, Felony, or other Crime, who shall flee from Justice, and be found in another State, shall on demand of the executive Authority of the State from which he fled, be delivered up, to be removed to the State having Jurisdiction of the Crime."

In simple terms, when someone commits a crime in one state (the "demanding state") and then flees to another state (the "asylum state"), the demanding state can request the return of the fugitive. The process involves the governor or a legal representative of the demanding state making a formal request to the governor of the asylum state. If the request is approved, the asylum state holds a hearing to establish the identity of the fugitive and ensure that the demand is constitutional and legally in order, then orders the fugitive's return to the demanding state for trial or punishment.

Despite the constitutional provision, there are federal statutes that provide the specific legal framework for how extradition is carried out between states. The relevant laws are found in the United States Code (U.S.C.), particularly 18 U.S.C. § 3182.

Extra: Extradition is an important legal mechanism that ensures individuals cannot simply escape legal responsibility for their actions by crossing state lines. It's based on the principle of cooperation between states to uphold the law and enforce justice. However, it's interesting to note that while the Constitution requires states to return fugitives, the procedure and specific circumstances can involve considerable legal complexity. Factors such as the seriousness of the crime, the individual's rights, and inter-state relations can influence the extradition process. Also, the governor of the asylum state does have some discretion and may refuse to extradite the fugitive if they believe that the extradition request is not made in good faith or for other specific legal reasons outlined in the state's laws or the federal statutes. There have been cases where issues such as potential human rights violations in the demanding state have played a role in extradition decisions.