The Seal of Confession? Is it immoral?

If a priest was told during confession that the murderer was speaking to him; in other words, a man told the priest he killed someone. Then, it is sealed through "The Seal of Confession" and is therefore, the priest is not allowed to tell law enforcement about the claim which by the way, is obstruction of justice.

These Christians use the church separate from state clause to their advantage here.

Also, if a priest is accused of sexual abuse (for example), then again through the Seal of Confession, he is not allowed to defend himself with a counter argument even though the truth is, he didn't sexually abuse anyone (again, this is just for example).

In both situations, the truth is concealed. Is it moral to essentially prevent the truth from coming out? What gives them (priests) the courtesy not to tell the truth? Jesus is "truth" isn't he?

Surely, it would be moral to come out and tell the truth in both situations, wouldn't it? Surely, transparency of truth and implementation of justice are more important than some Seal of Confession which Jesus never said himself was necessary.

A priest at my school explained the Seal of Confession to us and the above statements/arguments are my questions in response. I will give them tomorrow. I have no where else to post this but to the Atheism sub-reddit. So, any thoughts?