It wasn't the mob that handed Jesus to the Romans. It was one of Jesus's disciples Judas that led the Romans to Jesus.
It was the high priest that charged Jesus with blasphemy.
Mark 14:. 60 Then the high priest stood up before them and asked Jesus, "Are you not going to answer? What is this testimony that these men are bringing against you?"
61 But Jesus remained silent and gave no answer. Again the high priest asked him, "Are you the Christ, the Son of the Blessed One?"
62 "I am," said Jesus. "And you will see the Son of Man sitting at the right hand of the Mighty One and coming on the clouds of heaven."
63 The high priest tore his clothes. "Why do we need any more witnesses?" he asked.
64 "You have heard the blasphemy. What do you think?" They all condemned him as worthy of death.
65 Then some began to spit at him; they blindfolded him, struck him with their fists, and said, "Prophesy!" And the guards took him and beat him.