Plato, Laws

[867a] both as a rule done in passion, and most properly described as lying midway between the voluntary and the involuntary. None the less, each of these kinds tends to resemble one or other of these contraries; for the man who retains his passion and takes vengeance, not suddenly on the spur of the moment, but after lapse of time, and with deliberate intent, resembles the voluntary murderer; whereas the man who does not nurse his rage, but gives way to it at once on the spur of the moment and without deliberate intent, has a likeness to the involuntary murderer; yet neither is he wholly involuntary, but bears a resemblance thereto. [867b] Thus murders done in passion are difficult to define,—whether one should treat them in law as voluntary or involuntary. The best and truest way is to class them both as resemblances, and to distinguish them by the mark of deliberate intent or lack of intent, and to impose more severe penalties on those who slay with intent and in anger, and milder penalties on those who do so without intent and on a sudden. For that which resembles a greater evil must be more heavily punished, that which resembles a lesser evil [867c] more lightly. So our laws also must do likewise.

Clinias
They must, most certainly.

Athenian
Returning, then, to our task, let us make this pronouncement:—If a man with his own hand slay a free man, and the deed be done in rage without deliberate intent, he shall suffer such other penalties as it is proper for the man to suffer who has slain without passion, and he shall be compelled to go into exile for two years, thereby chastising his own passion. [867d] And he that slays in passion and with deliberate intent shall be treated in other respects like the former, but shall be exiled for three years—instead of two, like the other,—receiving a longer period of punishment because of the greatness of his passion. As regards the return home, in such cases it shall be on this wise. (It is a difficult matter to legislate for with exactness; for sometimes the more dangerous of the two murderers in the eye of the law might prove the more gentle and the gentler the more dangerous, and the latter might have committed the murder more savagely, the former more gently; though as a rule matters turn out in the way we have stated: [867e] so, regarding all these regulations the Law-wardens must act as supervisors). When the period of exile in each case has elapsed, they must send twelve of their number to the borders of the country to act as judges—they having made during the interval a still closer investigation into the actions of the exiles; and these men shall serve also as judges in regard to the matter of giving them pardon and admitting them back; and the exiles must abide by the verdicts of these magistrates.