Caiaphas was the high priest with Annas at the time of Jesus and was instrumental in his arrest, trial and death. As Jesus began to speak out against the Pharisees and religious leaders they looked for ways to dispose of him. Caiaphas was worried about Jesus’ popularity and plotted against him (John 11 :45-47).
He was the one who ripped his clothes at the trial after hearing what he considered to be blasphemy. This was punishable by the death penalty in Jewish law, but as Palestine was under Roman law, only Pilate could have passed that sentence (Matt 26:57-68).