Justifiable homicide

Lawful killing
Permissible murder

The concept of justifiable homicide in criminal law is a defense to culpable homicide (criminal or negligent homicide). Generally, there is a burden of production of exculpatory evidence in the legal defense of justification. In most countries, a homicide is justified when there is sufficient evidence to disprove (under the "beyond a reasonable doubt" standard for criminal charges, and "preponderance of evidence" standard for claims of wrongdoing, i.e. civil liability) the alleged criminal act or wrongdoing. The key to this legal defense is that it was reasonable for the subject to believe that there was an imminent and otherwise unavoidable danger of death or grave bodily harm to the innocent by the deceased when they committed the homicide. A homicide in this instance is blameless.

Source: Wikipedia

Article 336 of the Criminal Code of the Dominican Republic states that "homicide of the spouse is pardonable when the other spouse is caught in the act of adultery in the conjugal home, and the accused has killed either the spouse, his/her accomplice, or both".
At no time is the taking of another human life justifiable, murder is murder and justifications simply hide this fact.
The right to life implies the right to protect and defend one's own life or the life of another person against an unjust attack. Since the defence can only be effective if it is in proportion to the violence of the unjust attack, it is possible that in the act of defending oneself or another the victim may kill the assailant.
(E) Emanations of other problems