Matthew 27:11 Meanwhile Jesus stood before the governor, and the governor asked him, “Are you the king of the Jews?”
“You have said so,” Jesus replied.
12 When he was accused by the chief priests and the elders, he gave no answer. 13 Then Pilate asked him, “Don’t you hear the testimony they are bringing against you?” 14 But Jesus made no reply, not even to a single charge—to the great amazement of the governor.
15 Now it was the governor’s custom at the festival to release a prisoner chosen by the crowd. 16 At that time they had a well-known prisoner whose name was Jesus Barabbas. 17 So when the crowd had gathered, Pilate asked them, “Which one do you want me to release to you: Jesus Barabbas, or Jesus who is called the Messiah?” 18 For he knew it was out of self-interest that they had handed Jesus over to him.
19 While Pilate was sitting on the judge’s seat, his wife sent him this message: “Don’t have anything to do with that innocent man, for I have suffered a great deal today in a dream because of him.”
20 But the chief priests and the elders persuaded the crowd to ask for Barabbas and to have Jesus executed.
21 “Which of the two do you want me to release to you?” asked the governor.
“Barabbas,” they answered.
22 “What shall I do, then, with Jesus who is called the Messiah?” Pilate asked.
They all answered, “Crucify him!”
23 “Why? What crime has he committed?” asked Pilate.
But they shouted all the louder, “Crucify him!”
24 When Pilate saw that he was getting nowhere, but that instead an uproar was starting, he took water and washed his hands in front of the crowd. “I am innocent of this man’s blood,” he said. “It is your responsibility!”
25 All the people answered, “His blood is on us and on our children!”
26 Then he released Barabbas to them. But he had Jesus flogged, and handed him over to be crucified.
According to the site at "Got Questions", Jesus Barrabus was a murderer and a rabble rouser. He was a Jewish prisoner. Pilate chose Jesus Barrabus because he was very, very, guilty. But, according to the site, Pilate was surprised they chose Jesus the Messiah. Pilate had been trying to do what his wife told him to do and throw the crucifixion away from Jesus the Messiah. But both God and Satan work in mysterious ways. The crowd was seeded with haters and Jesus Barrabus was let out on the streets to kill again.
They play this scenario on "Have Gun Will Travel" a lot. It's the mean guy who has something wicked hanging over everyone in town. Maybe he helped them hide something from those Romans. There was a "hangman" series on "Rawhide" the other day. All the people in town were afraid of the guy they were going to hang, so they almost killed the hangman. Pilate wanted no part of putting his hangman in that situation. Perhaps the people in the crowd were afraid if they didn't free Jesus Barrabus, his cohorts would kill their family in repayment.
The temple priests, elders, teachers of the law, and rabbis ran the church. They could excommunicate people from the temple for their erroneous decisions. Being thrown out of Temple was a horrible fate. Friends would not welcome them anymore, for fear. Enemies didn't even want anything to do with them, for hate. Vendors would not deal fairly with them, because of fear of losing their spot in the Temple courtyard. If the vendors wouldn't deal with them, they couldn't purchase a "sin sacrifice" and that meant they were doomed worse than Job.
So, Pilate washed his hands clean. Wimp....