A.T. Robertson Commentary Acts 25:16

"To whom I answered, that it is not the custom of the Romans to give up any man, before that the accused have the accusers face to face, and have had opportunity to make his defense concerning the matter laid against him." — Acts 25:16 (ASV)

It is not the custom of the Romans (οτ ουκ εστιν εθος Ρωμαιοις). If a direct quotation, οτ is recitative as in Authorized Version. Canterbury Revision takes it as indirect discourse after απεκριθην (I answered), itself in a relative clause (προς ους) with the present tense (εστιν, is) preserved as is usual. There is a touch of disdain (Furneaux) in the tone of Festus. He may refer to a demand of the Jews before they asked that Paul be brought to Jerusalem (25:3). At any rate there is a tone of scorn towards the Jews.

Before that the accused have (πριν η ο κατηγορουμενος εχο). This use of the optative in this temporal clause with πριν η instead of the subjunctive αν εχη is in conformity with literary Greek and occurs only in Luke's writings in the N.T. (Robertson, Grammar, p. 970). This sequence of modes is a mark of the literary style occasionally seen in Luke. It is interesting here to note the succession of dependent clauses in verses 14-16.

The accusers face to face (κατα προσωπον τους κατηγορους). Same word κατηγορος as in 23:30,35; 25:18. This all sounds fair enough.

And have had opportunity to make his defence concerning the matter laid against

him (τοπον τε απολογιας λαβο περ του εγκληματος). Literally, "And should receive (λαβο optative for same reason as εχο above, second aorist active of λαμβανω) opportunity for defence (objective genitive) concerning the charge" (εγκληματος in N.T. only here and 23:19 which see).