In what situations can the Federal government exercise command authority over state or local governments?

Under theUnited States Constitutionand theStafford Act, the federal government generally doesnotexercise "Command Authority" over state or local governments. The principle ofTiered Responsedictates that incidents are managed at the lowest possible jurisdictional level, with the federal government providing "support and coordination." However, in specific situations involvingBio-terrorism(Option C) or other acts of terrorism, the federal government may assume a lead "Command" role through theFBI(for investigation/law enforcement) and theDepartment of Defense(if the situation is deemed an act of war or a threat to national security).

In a natural disaster (Option A) or a pandemic (Option B), the federal government's role is governed byEmergency Support Functions (ESFs)where they act as "Coordinators." For example, during a pandemic, the CDC provides guidance and the ASPR manages the stockpile, but the actual "Police Power" (the authority to mandate masks or lockdowns) remains with the Governors of the states. It is only when an incident transitions from a "Civil Disaster" to a "National Security Threat" (like a biological attack) that the federal government invokes specific authorities under theNational Strategy for Homeland Securityto take a more direct "Command" stance regarding the neutralization of the threat.

For theCEDPcandidate, it is crucial to understand that even when the federal government "takes the lead" in a bio-terrorism event, they typically do so through aUnified Commandstructure. They do not "order" local fire departments or police to act; rather, they integrate their assets to solve a problem that is beyond the scope of a single state. The only exception where "Command" is truly vertical from the federal level is during afederalization of the National Guardor in "Exclusive Federal Jurisdictions" (like military bases or federal buildings). Understanding these jurisdictional boundaries prevents "Command Confusion" during a multi-state crisis and ensures that local leaders understand they retain their constitutional authority even when a massive federal presence is on the ground.