Was Pontius Pilot really guilty ?

He was guilty of being ignorant. Thank God that he was since if Jesus wouldn't have been sacraficed we would not have hope of forgiveness of our sins.

Yes, he was, washing his hands did not wash away his guilt, nor did his giving in to the crowds demand for Barabus relieve Pilot of his guilt. He, and the religeous leaders of the day could not hide their guilt behind the letters of the law that they twisted. The thing is- we are all guilty also, those men may have put Christ on that cross, but it was your and mine sin who kept him there.