○ Reasonable mistake? This is ok, because the situation is urgent. ■ Not if they are delusional though ○ Innocent Third Parties? ■ Person under attack is not liable for battery unless the person under attack “realizes or should realize that his act creates an unreasonable risk of causing such harm” ● Shooting a gun in public to hit a person but hitting an innocent bystander creates unreasonable risk ○ Defense of Others ■Person about to be attacked must have the privilege to act in self defense and the other person’s intervention must be necessary!

★ Defense of Property An actor is privileged to use reasonable force, not intended or likely to cause death or serious bodily harm, to prevent or terminate another’s intrusion upon the land or chattels if: (a) The intrusion is not privileged or the other intentionally or negligently causes actor to believe that it is not privileged (b) The actor reasonably believes intrusion can be prevented or terminated only by the force used, AND (c) Actor has first requested the other to desist and the other has disregarded the request. ○ The amount of force can NEVER be deadly force ■ Human life is worth more than property ○ Cannot use passive deadly force mechanism (Katko v. Briney) ■ Can use reasonable protective devices like barbed wire ● Or even a spring gun that paints the intruder ○ Deadly force in home is often allowed to prevent forcible entry ○ IF ways to terminate intrusion w/o force, they must be used ○ Must first consider whether it is prudent to ask the intruder to leave ★ Necessity: conditional and incomplete b/c will still have to pay for damage caused ○ Protects against punitive damages and one is allowed to use it and pay later (the owner does not have the right to interfere w/ intruder ○ Ex. Vincent v. Lake Erie Transportation CO.: “A starving man may, without moral guilt, take what is necessary to sustain life but it could hardly be said that the obligation would not be upon such person to pay the value of the property so taken when he became able to do so.” ★ Public Necessity: when a person acts to further the public good, serves as a complete defense. Person taking or destroying property need not pay for the damage caused ○ Occurs when natural forces or third parties require destruction of property to save the lives or property of other people. FOR PUBLIC BENEFIT ■ Mouses’ case: throwing off another person’s property from a ship in order to prevent the ship from sinking and therefore saving lives ■ Animal control officer shooting a rabid dog that was threatening a crowd of people will not have to pay compensation to the owner. ___________________________________________________________________________ NEGLIGENCE : unintentional harms I. Duty: D has a duty to everyone to avoid creating an unreasonable risk of harm foreseeable plaintiffs.