Defense of others
The rules are the same when force is used to protect another from danger. Generally, the defendant must have a reasonable belief that the third party is in a position where they would have the right of self-defense. For example, a person who unknowingly chances upon two actors practicing a fight would be able to defend their restraint of the one that appeared to be the aggressor. However, in many jurisdictions a person who causes injury in defense of another may be liable to criminal and civil charges if such defence turned out to be unnecessary. Most[weasel words] courts have ruled that such a defense cannot be used to protect friends or family members who have engaged in an illegal fight. Likewise, one cannot use this to aid a criminal.[citation needed][dubious – discuss]
Defense of others is called pikuach nefesh in Jewish law. One may violate most negative commandments of the Torah in order to save someone's life.
