There are specific circumstances in which you are legally allowed to use deadly force. In Pennsylvania, you are granted the right to use deadly force if you believe that it is necessary to protect yourself against death, serious bodily injury, kidnapping, or sexual intercourse compelled by force or threat. Deadly force is not to be used as an immediate response, but rather as last resort. You are not authorized to use deadly force in protection to the acts previously stated if you were the initial aggressor of the situation or you are able to retreat safely in response. In Pennsylvania, you are not obligated to retreat from your home and in some circumstances your work. This is known as a Castle Doctrine.