Matthew 27:15

Now at the feast the governor was wont to release, unto the multitude one prisoner, whom they would. And they had then a notable prisoner, called Barabbas. When therefore they were gathered together, Pilate said unto them, Whom will ye that I release unto you? Barabbas, or Jesus who is called Christ?

The Fourth Effort of Pilate to Release Jesus

No doubt Pilate thought they would choose Christ; but he had reckoned without consideration of the fanatical hatred of the leaders against Christ. Barabbas was a notorious seditionist and robber (Mark 15:7), the leader of a group who had made an insurrection against Rome (presumably). His crimes were murder, robbery, and sedition; and Pilate's strategy at that point was directed to forcing a choice between such a man and Christ. Under the circumstances, the choice of Barabbas would have strong overtones of disloyalty to Caesar which the Pharisees had so lately professed; but if Pilate counted on such a deterrent to the choice of Barabbas, he was mistaken.

Did Barabbas know of that proposal? If so, he must have felt that he had practically no chance of being chosen over one whose reputation as a prophet, healer, and holy person was so widespread. Since the condemnation of other robbers resulted in their crucifixion, it is safe to assume that the same fate awaited Barabbas, except for Pilate's proposal to pair him with Christ for the honor of being released for Passover.