No one is happy who lives such a life that his murder would be no crime, but would rather redound to the credit of his murderer.

[Beatus est nemo qui ea lege vivit, ut non mode impune, sed etiam cum summa interfectoris gloria interfici potest.]

Marcus Tullius Cicero (106-43 BC) Roman orator, statesman, philosopher

Philippics [Philippicae; Antonian Orations, No. 1, ch. 14 / sec. 35 (1.14/1.35) (44-09-02 BC) [ed. Harbottle (1906)]
    (Source)

See Achebe.

(Source (Latin)). Other translations:

No one is happy who lives upon such terms that his death not only goes unpunished, but even brings the highest glory to his murderers.
[tr. King (1877)]

No one is happy who holds his life on such terms that he may be slain, not only with impunity, but even to the greatest glory of his slayer.
[tr. Ker (Loeb) (1926)]

No one is happy who lives on such terms that he may be put to death not merely with impunity, but even to the great glory of his slayer.
[tr. Yonge (1903)]

No one is happy whose life is lived by this law: not only can someone kill him with impunity, but the killer gains enormous fame from the deed.
[tr. McElduff (2011)]