Pilot didn't want to kill Jesus he had the Jews decide. The Jews chose Barabbas instead of Jesus. It was the Jews that got Judas to betray Jesus for 30 pieces of silver. Jesus obviously thought it was Israel responsible because it was Israel that he judged. 1 Thess.2:14-16 - the Jews were told they killed Jesus. The Romans did their part but it was Israel that was responsible in the eyes of God. They were behind it.
14For you, brothers and sisters,* became imitators of the churches of God in Christ Jesus that are in Judea, for you suffered the same things from your own compatriots as they did from the Jews, 15who killed both the Lord Jesus and the prophets,* and drove us out; they displease God and oppose everyone 16by hindering us from speaking to the Gentiles so that they may be saved. Thus they have constantly been filling up the measure of their sins; but God’s wrath has overtaken them at last.*