and in Yerushalayim I did so. After receiving authority from the head cohanim, I myself threw many of God’s people in prison; when they were put to death, I cast my vote against them.
Earthly authority does not equal morality. The authority of the corrupt cohanim and Shaul lead to murder that went against Torah. There is nothing moral in that. People can often confuse the official Right to act with moral Right, that is a dangerous mistake.