Pilate tried to acquit Jesus
In comparing the Gospel accounts of Jesus' trial, we find that Pilate tried at least 4 times to have Jesus released:
See Luke 23:22
For the third time he spoke to them: “Why? What crime has this man committed? I have found in him no grounds for the death penalty. Therefore I will have him punished and then release him.”
& the apparently subsequent John 19:12 (this appears to correspond to Luke 23:23)
From then on, Pilate tried to set Jesus free, but the Jewish leaders kept shouting, “If you let this man go, you are no friend of Caesar. Anyone who claims to be a king opposes Caesar.”
Pilate questions Jesus, sends Him to Herod, offers to release Him in honor of the feast, and parries each attempt by the Sanhedrin to execute Jesus.
Apparent motivations include:
His wife's dream (Matt 27:19)
His own fear at the claims made by & about Jesus (John 19:8)
The apparently recent instructions from Tiberius to not execute innocent people (see Philo "On the Embassy to Gaius" ch. 24 here)
Pilate seems pretty keen not to execute Jesus. After the Sanhedrin tells him "you are no friend of Caesar" & "we have no king but Caesar" Pilate's resolve finally crumbles.
- Why was this statement about Caesar such a powerful trump card?
- What consequences would Pilate have faced if he had refused to comply?
Important note about this question: this is not a question about all Jews at the time or all Jewish people in general. This is a question about why the interactions between a handful of very specific people - the Sanhedrin and Pilate - played out the way they did.
Addendum from my research:
In this article Paul Maier suggests that Pilate had some level of protection while the powerful Roman official Sejanus was head of the Praetorian Guard (and Tiberius' right hand man), and thus could get away with some of the atrocities noted by Josephus & Luke.
Then Sejanus (along with a number of associates) was executed for conspiracy and Pilate had to be very careful not to incur Tiberius' ire. Pilate may have already been on strained terms with Rome before the trial of Jesus; thus, a delegation being sent to Rome was a significant and credible threat.