'Legal' in the Bible

Philip found Nathanael and told him, “We have found the One Moses in the Law and also the Prophets wrote about—Jesus from Nazareth, the son of Joseph [according to public record].”

So Pilate told them, “Take Him yourselves and judge Him according to your law.”“It’s not legal for us to put anyone to death,” the Jews declared.

The Jewish leaders told him, "It is not legal for us to put anyone to death." This was to fulfill what Jesus had said when he indicated the kind of death he was to die.