What must occur for a Canadian fugitive to be extradited to the United States?

A valid U.S. warrant must be obtained is the correct answer because the extradition process between the United States and Canada hinges on the existence of a valid warrant that establishes the legal basis for the request. This warrant serves as official documentation that there is a legitimate claim against the individual, allowing the necessary legal proceedings to take place.

In the context of extradition, the U.S. must provide documentation that officially requests the return of the fugitive, which typically includes charges and evidence. Although international treaties, court consent, and possibly even political considerations play a role in the larger context of extradition, the initial and crucial step that enables the process to move forward is having a valid warrant. Without this, the legal framework required to justify extradition is lacking, which would impede the capacity to proceed.