From Why Was Jesus Crucified? [gated link]
What is clear is that Jesus was killed on political charges, and nothing else. Many people seem to think that Jesus ran afoul of the authorities because he committed blasphemy or offended the religious sensitivities of the Jewish leaders of his day (Pharisees, e.g.; or the Sadducees of the Sanhedrin; etc.). But in fact, the Romans didn’t care TWIT about Jewish blasphemy or about internal Jewish disputes about doctrine and/or practice. Moreover, the record is crystal clear what the charges against Jesus were. They were political in nature. He had been calling himself the King of the Jews.