Luke 23:11 (KJB)
And Herod with his men of war set him at nought, and mocked him, and arrayed him in a gorgeous robe, and sent him again to Pilate.
Since Jesus gave Herod no answers nor did He perform a miracle for him, Herod probably took it as Jesus being a phony and that all the stories about Him were false. So just like the Romans will do, Herod’s bodyguards or soldiers who accompanied him to Jerusalem had now begun to mock Jesus. They set Him at nought, that is, they saw Him as the least esteemed or of a lower class and basically treated Him with contempt. They mocked Jesus because they heard that He was king of the Jews, so they placed a very nice robe on Him, something, like a king would wear and then returned Him to Pilate.
Luke 23:12 (KJB)
And the same day Pilate and Herod were made friends together: for before they were at enmity between themselves.
Pilate and Herod had become friends that day because of their mistreatment of Jesus. It is not known why they fell out of disfavor with one another and it is also not known how far their friendship had progressed. Herod Antipas only ruled over about one third the size kingdom that Herod the Great had ruled over. It is possible that Pilate did not respect the rule of Herod because it was so small.
Luke 23:13 (KJB)
And Pilate, when he had called together the chief priests and the rulers and the people,
Jesus was now back in the court of Pilate. Pilate had now called all the chief priests and the rulers of Israel back to the court. The people were also assembled at this place. Pilate was maybe hoping that the people would favor Jesus and nothing would be done to Him. However, nothing had changed and Jesus was still being held on the same charges that were against Him when He went to Herod. There is no indication that Pilate had questioned Jesus this time although he had made several appearances in the judgment hall, so the possibility exists that Pilate could have re-examined Him privately to clear Him.
Luke 23:14 (KJB)
Said unto them, Ye have brought this man unto me, as one that perverteth the people: and, behold, I, having examined him before you, have found no fault in this man touching those things whereof ye accuse him:
Then Pilate spoke to the crowd and to the leaders reiterating his prior findings that Jesus was totally innocent of all the charges they brought against Him. They had claimed that Jesus perverted the people, that is, mislead or turned them away from obedience to insurrection but Pilate had examined Jesus in front of the leaders and the crowd and he found absolutely no evidence of any type of insurrection. Pilate would have been well aware of any such event. The truth was that Jesus had no soldiers, killed no one, had no peers in rebellion, did not even partake in any rebellion, etc. Pilate now knew that the charges against Jesus had been faked plus he did not want to get in the middle of any of their theological squabbles. He states plainly that he found no fault in Jesus concerning any of the accusations.
Luke 23:15 (KJB)
No, nor yet Herod: for I sent you to him; and, lo, nothing worthy of death is done unto him.
Then he tells the crowd that he even sent Jesus to Herod for examination and Herod had found no fault in Jesus worthy of death. Maybe Herod had claimed that he found some type of small charge against Jesus but not big enough to warrant death. Pilate went from “no fault” to “worthy of death,” which means Herod may have influenced Pilate’s own findings. If he did, then Herod also created a false charge against Jesus.