προπιστόομαι
From LSJ
τεκμαιρόμενοι προκατηγορίας οὐ προγεγενημένης → deducing from the fact that there was no previous accusation
English (LSJ)
Pass.,
A to be made credible before, pf. προπεπίστωμαι S.E.P.1.116, M.8.122,261; ἐκ φαινομένου π. τὸ ἄδηλον ib.62.