Albert Barnes Commentary John 18:30

"They answered and said unto him, If this man were not an evildoer, we should not have delivered him up unto thee." — John 18:30 (ASV)

If he were not a malefactor—meaning, a violator of the law. They implied: "If we had not determined that he was such, and was worthy of death (Matthew 26:66)..." From this, it appears that they did not deliver him up to be tried, but hoped that Pilate would at once give sentence that he should be executed according to their request.

It is probable that in ordinary cases the Roman governor was not accustomed to make a very strict inquiry into the justice of the sentence. The Jewish Sanhedrin tried cases and pronounced sentence, and the sentence was usually approved by the governor. However, in this instance, Pilate, evidently contrary to their expectations, proceeded himself to rehear and retry the case.

He had doubtless heard of the miracles of Jesus. He seems to have been strongly prepossessed with the belief of his innocence. He knew that they had delivered him up out of mere envy (Matthew 27:18), and therefore he inquired of them the nature of the case, and the kind of charge which they expected to substantiate against him.