I don't know if this is still law in Louisiana.
LA Rev Stat § 14:20
§20. Justifiable homicide
A. A homicide is justifiable:
(1) When committed in self-defense by one who reasonably believes that he is in imminent danger of losing his life or receiving great bodily harm and that the killing is necessary to save himself from that danger.
(2) When committed for the purpose of preventing a violent or forcible felony involving danger to life or of great bodily harm by one who reasonably believes that such an offense is about to be committed and that such action is necessary for its prevention. The circumstances must be sufficient to excite the fear of a reasonable person that there would be serious danger to his own life or person if he attempted to prevent the felony without the killing.
(3) When committed against a person whom one reasonably believes to be likely to use any unlawful force against a person present in a dwelling or a place of business, or when committed against a person whom one reasonably believes is attempting to use any unlawful force against a person present in a motor vehicle as defined in R.S. 32:1(40), while committing or attempting to commit a burglary or robbery of such dwelling, business, or motor vehicle.
(4)(a) When committed by a person lawfully inside a dwelling, a place of business, or a motor vehicle as defined in R.S. 32:1(40), against a person who is attempting to make an unlawful entry into the dwelling, place of business, or motor vehicle, or who has made an unlawful entry into the dwelling, place of business, or motor vehicle, and the person committing the homicide reasonably believes that the use of deadly force is necessary to prevent the entry or to compel the intruder to leave the premises or motor vehicle.
(b) The provisions of this Paragraph shall not apply when the person committing the homicide is engaged, at the time of the homicide, in the acquisition of, the distribution of, or possession of, with intent to distribute a controlled dangerous substance in violation of the provisions of the Uniform Controlled Dangerous Substances Law.