Which agency is involved when an individual is arrested for a financial crime related to the U.S. mail?

When an individual is arrested for a financial crime related to the U.S. mail, the U.S. Postal Service is involved primarily because it oversees the operation and administration of the mail system, which includes the investigation of crimes that occur related to mail fraud and other postal offenses. The U.S. Postal Inspection Service, a branch of the U.S. Postal Service, is responsible for enforcing laws that protect the Postal Service and the mail system from fraud and other illegal activities, making it specifically relevant to cases involving financial crimes linked to the mail.

While other agencies like the FBI and the U.S. Secret Service may also be involved in broader financial crime investigations, their jurisdiction typically extends beyond postal crimes specifically. The Federal Bureau of Prisons is not directly involved in the investigation of crimes but rather manages the incarceration of individuals convicted of federal offenses. Thus, the U.S. Postal Service is the primary agency that would deal with financial crimes that utilize or involve the U.S. mail system.