Plutarch, Sayings of the Romans (Moralia 200e) Scipio the Younger 13
“When [P. Africanus] saw Gaius Licinius approaching, he said ‘I know that this man has committed perjury, but since no one else is accusing him, I can’t be accuser and judge at the same time”
Γάιον δὲ Λικίνιον ἰδὼν παρερχόμενον, “οἶδα,” ἔφη, “τοῦτον ἐπιωρκηκότα τὸν ἄνδρα· μηδενὸς δὲ κατηγοροῦντος, οὐ δύναμαι κατήγορος αὐτὸς εἶναι καὶ δικαστής.”
Cicero, Pro Cluentio 134
“It seems impossible to me not to mention the example of the great and most famous man P. Africanus who, when he was in the office of censor of knights, oversaw he appearance of G. Licinius Sacerdos. When he came forward he said in a voice loud enough for the whole assembly to hear that this man had committed perjury intentionally and that if anyone would bring charges against him, he would provide his own testimony.
When no one spoke to do so, he told him to “lead on his horse.” In this way, one whose judgment the Roman people and foreign states were accustomed to trusting was not certain enough with his own knowledge to judge another.”
Non enim mihi exemplum summi et clarissimi viri, P. Africani, praetereundum videtur: qui cum esset censor et in equitum censu C. Licinius Sacerdos prodisset, clara voce, ut omnis contio audire possit, dixit se scire illum verbis conceptis peierasse: si qui contra vellet dicere, usurum esse eum suo testimonio: deinde cum nemo contra diceret, iussit equum traducere. Ita is, cuius arbitrio et populus Romanus et exterae gentes contentae esse consuerant, ipse sua scientia ad ignominiam alterius contentus non fuit.
Cicero seems to take a different lesson from this than others. Where other examples seem to imply Scipio avoiding making a charge based on ethical restraints, Cicero implies that Scipio did not have enough faith in his own knowledge to besmirch a man’s reputation. Valerius Maximus echoes Plutarch.
Val. Max. Memorable Deeds and Words 4. 1.10b
“But then, because no one took up the charge, [Africanus] said “Take your horse across, Sacerdos and be free of the censor’s judgment so that I may not seem to play the part of accuser, witness, and judge against you.”
sed nullo ad id negotium accedente ‘transduc equum’ inquit, ‘Sacerdos, ac lucrifac censoriam notam, ne ego in tua persona et accusatoris et testis et iudicis partes egisse videar.’