What is necessary for an actor to be justified in using force or deadly force while defending a third person?

The justification for using force or deadly force in defense of a third person hinges on the belief in an immediate threat to that individual. When an actor perceives that a third party is facing an imminent danger, they are empowered to intervene to prevent harm from occurring. This belief must be reasonable, meaning that a reasonable person in the same situation would also perceive the threat as immediate and significant. The law generally allows individuals to step in to protect others if they have a genuine and reasonable belief that the third party is at risk of harm.

Other considerations, such as a request for protection or familial relationships, do not necessarily play a crucial role in justifying the use of force. The essence of self-defense or defense of others is centered on the perceived necessity of immediate protection against a threat, rather than the nature of the relationship or prior requests for help. It is also important that the actor does not act too aggressively or exceed what is reasonable in the circumstances; however, the core factor remains the belief in a credible, immediate threat to the third party.