@SAKURARadiochan @sickburnbro @doctorsex @alchemy Just weighing in.

Pilate didn't want to, but when push came to shove, he was more afraid of the Jews than he was of Jesus. Pilate knew he was killing an innocent man. He didn't want to, but his own self-interests took priority.

Like Radiochan said, the buck stopped with him.

Editorializing:

Pilate was also probably afraid the Jews would riot, and it would be blamed on his decision, even if the caesar found no fault when Christ was brought before him.

With that said, it's both the fault of Pilate and the Jews.