Note 56 — Chapter XXIII · On Doubtful Causes.
A. C. (Archibald Colin) Campbell translation
Thus letters of marque and reprisal, by which individuals are enabled to redress their own wrongs, must issue from the sovereign power, otherwise the hostilities of such individuals would be unlawful. So that here the ACTION would be unlawful, that is unjust, unless performed by an AGENT, who had a commission from public authority.