Passage 7.14.1
ἀφίκοντο δὲ ἐς τὴν Ἑλλάδα καὶ οἱ ἀποσταλέντες ἐκ Ῥώμης Λακεδαιμονίοις δικασταὶ καὶ Ἀχαιοῖς γενέσθαι, ἄλλοι τε καὶ Ὀρέστης· ὁ δὲ τούς τε ἐν ἑκάστῃ πόλει τῶν Ἀχαιῶν ἔχοντας τὰς ἀρχὰς καὶ Δίαιον ἐκάλει παρʼ αὑτόν. ἀφικομένοις δὲ ἔνθα ἔτυχεν αὐτὸς ἐσῳκισμένος, ἀπεγύμνου τὸν πάντα σφίσιν ἤδη λόγον, ὡς δίκαια ἡγοῖτο ἡ Ῥωμαίων βουλὴ μήτε Λακεδαιμονίους τελεῖν ἐς τὸ Ἀχαϊκὸν μήτε αὐτὴν Κόρινθον, ἀφεῖσθαι δὲ καὶ Ἄργος καὶ Ἡράκλειαν τὴν πρὸς Οἴτῃ καὶ Ὀρχομενίους Ἀρκάδας συνεδρίου τοῦ Ἀχαιῶν· γένους τε γὰρ αὐτοῖς οὐδὲν τοῦ Ἀχαιῶν μετεῖναι καὶ ὕστερον τὰς πόλεις προσχωρῆσαι ταύτας πρὸς τὸ Ἀχαϊκόν.
The judges sent from Rome to arbitrate between the Lacedaemonians and the Achaeans also arrived in Greece; among them was Orestes. He summoned before him Diaeus and those holding office in each of the Achaean cities. When they gathered in the place where he himself happened to be residing, he laid out all of the Romans' decision before them, asserting that the Roman senate deemed it right neither for the Lacedaemonians nor Corinth to belong to the Achaean League; he also declared that Argos, Heracleia near Oeta, and the Arcadian Orchomenians should be exempted from the Achaean synod. For, he said, these peoples shared no common lineage with the Achaeans and had only later attached their cities to the Achaean alliance.