A.T. Robertson Commentary Acts 28:18

"who, when they had examined me, desired to set me at liberty, because there was no cause of death in me." — Acts 28:18 (ASV)

When they had examined me (ανακριναντες με). First aorist active participle of ανακρινω, the same verb used already in 24:8; 25:6,26 of the judicial examinations by Felix and Festus.

Desired (εβουλοντο). Imperfect middle of attempted action or picture of their real attitude. This is a correct statement as the words of both Felix and Festus show.

Because there was (δια το--υπαρχειν). Accusative case with δια (causal use) with the articular infinitive, "Because of the being no cause of death in me" (εν εμο, in my case, αιτια, usual word for crime or charge of crime).