Final answer:
The individual responsible for establishing command at a scene is designated through a hierarchy of authority, similar to military or emergency response systems like the Incident Command System.
Step-by-step explanation:
The individual at the scene responsible for establishing command is designated through a hierarchy of authority. This hierarchy is akin to a chain of command within an organization in which every member knows who to report to. For example, in a military setting, an officer would be given the authority by higher command to take charge at a scene. This is reflective of the practices adopted following historical acts, such as the military reconstruction act, which assigned a federal military commander to oversee regions during reconstruction.
In emergency response situations, the Incident Command System (ICS) is typically employed, which provides a standardized approach to the command, control, and coordination of emergency response. Here, the individual who assumes command is often the first responder at the scene with the highest rank or the greatest experience in managing emergencies. The designated commander's responsibility is to organize the response efforts and ensure the safety and efficiency of the operation. The hierarchy of authority ensures clear reporting relationships and eliminates confusion on the scene.