MA Castle Doctrine
Massachusetts General Law, Chapter 278, Section 8(a): In the prosecution of a person who is an occupant of a dwelling charged with killing or injuring one who was unlawfully in said dwelling, it shall be a defense that the occupant was in his dwelling at the time of the offense and that he acted in the reasonable belief that the person unlawfully in said dwelling was about to inflict great bodily injury or death upon said occupant or upon another person lawfully in said dwelling, and that said occupant used reasonable means to defend himself or such other person lawfully in said dwelling. There shall be no duty on said occupant to retreat from such person unlawfully in said dwelling.
A couple of things to note:
Deadly Force: Force likely or intended to cause death or great bodily harm whether or not death actually occurs.
Self Defense: In general, the right to protect one’s person against an injury attempted by another. In MA the courts have taken the position that self defense using deadly force is justified only if the individual being attacked has a reasonable belief that he or she is in danger of death or serious bodily harm. Otherwise reasonable force (which is non lethal force such as fists) can be used to repel a non-lethal attack. However, as applies to castle doctrine, reasonable force is not protected and so therefore cannot be relied upon if someone enters your home and threatens you with only fists.
Dwelling: A place where an individual is temporarily or permanently residing. It has to be a permanent structure, your home, apartment, cottage, and under some circumstances can include a hotel/motel room. Note: a dwelling cannot be a motor home, tent, or boat because they are not permanent structures. Anyone using deadly force in one of these will not be protected by this law.
An ‘occupant’ is an individual who has some sort of possessory interest in the property, i.e. a tenant or owner.
If a criminal is unlawfully in your dwelling, and shows the intent to inflict serious bodily injury or death upon you or any other individual lawfully in your dwelling there is no duty of said occupant to retreat from the criminal unlawfully in that dwelling.
Please note: If the criminal intruder is not threatening death or serious bodily injury, the occupant will not be covered by this law and could be charged with murder or manslaughter for using deadly force against said criminal. To be protected by this law an occupant that is prosecuted for using deadly force has the burden of producing a claim of self-defense. Once the occupant shows proof it will be upon the prosecution to prove otherwise.