"Castle Doctrine" generally encompasses the idea that a person does not have a duty to retreat from the residence he lawfully occupies before using force in self-defense or defense of another. Additionally, there is no duty to retreat if a person is lawfully in his vehicle or is lawfully an occupant in a vehicle owned by an immediate family member of that person.

However, being a lawful occupant of a residence or vehicle is not a license to use deadly force against an attacker. The person who is attacked, without fault of his own, may use deadly force only if he reasonably and honestly believed that deadly force was necessary to prevent serious bodily harm or death. If the person does not have this belief, he should not use deadly force. Again, if it does not put your life or the life of others in danger, you should withdraw from the confrontation if it is safe for you to do so.

The law presumes you to have acted in self-defense or defense of another when using deadly force if the victim had unlawfully and without privilege entered or was in the process of entering the residence or vehicle you occupy. The presumption does not apply if the defendant was unlawfully in that residence or vehicle. The presumption does not apply if the victim had a right to be in, or was a lawful resident of, the residence or vehicle.

The presumption of self-defense is a rebuttable presumption. The term "rebuttable presumption" means the prosecutor, and not the defendant, carries the burden of producing evidence contrary to the facts that the law presumes. However, a rebuttable presumption does not relieve the defendant of the burden of proof. If the prosecutor provides sufficient evidence to prove that the defendant created the confrontation or that the use of deadly force was not reasonably necessary to prevent death or great bodily harm, then the presumption of self-defense no longer exists. Statutory Reference(s): ORC 2901.05 sets forth the rebuttable presumption. ORC 2901.09(B) establishes that there is no duty to retreat before using force if a person is a lawful occupant of his vehicle or a lawful occupant in a vehicle owned by an immediate family member.