ἀληθευτικός
From LSJ
μηδενί δίκην δικάσῃς πρίν ἀμφοῖν μῦθον ἀκούσῃς → do not give your judgement on anything until you have heard a speech on both sides
English (LSJ)
ή, όν,
A truthful, frank, candid, Arist.EN1127a24, al.; τὸ ἀ. Hierocl.in CA2p.422M. Adv. -κῶς Eust.385.6, etc.