Redirected aggression occurs when a dog:

Redirected aggression occurs when a dog displays aggressive behavior towards a person or another animal that is not the original target of its frustration or anger. This typically happens when a dog is aroused or agitated by a specific stimulus, such as another dog or a particular situation, but instead of confronting that stimulus directly, it redirects its aggression towards a nearby person or animal.

In this context, when a dog shows aggression towards someone attempting to intervene, it is reacting to the stress or agitation that the initial trigger has caused. This can happen if the dog feels cornered or anxious, causing it to lash out at the nearest target, which can be a human trying to help or calm the situation.

The intricacies of redirected aggression demonstrate how a dog's emotional state can impact its behavior in ways that might not directly involve the source of its frustration. Understanding this concept is crucial for anyone working with dogs, as it emphasizes the need for caution when intervening in potentially aggressive encounters.