Absolutely, we all have lived different degrees of sinful lives, and I would argue my degree would be the highest. Glory be to the mercy of God that we are able to still work.
Are you condemning others or defending God's law?
Let me ask you, if you told someone who was guilty of 1st degree murder that they would either get the death penalty or 25 years to life in jail would you be condemning them? Would you be judging them?
I'm only going to respond to the one question you asked..."Are you condemning others or defending God's law?"
My answer would be that I do defend God's law, but God is the one who has the ability to condemn in an absolute sense. I cannot say for certain that a soul in in Hell, even though it may be the most likely scenario (as in the case of Elvis). God is not going to pay any attention to what we may believe about the state of a particular soul at the time of death. Only He is privy to that knowlege regarding the state of a soul. Only God decides who will go to Hell, Heaven, or Purgatory. It isn't up to us.
However, a priest has the ability to decide whether to give extreme unction, or forgive sins, etc., when a person is preparing for death. So there is a human judgement involved, of course, at the time of death, or any other time, too. And of course, there are circuмstances when a fallen Catholic may not have a funeral Mass, or be buried in a Catholic cemetery. I certainly believe in that.
But my understanding is that the Church herself cannot say for certain that a particular soul in in Hell. It may be very likely, but not absolutely certain. Correct me if I'm wrong about that.
Upholding God's law doesn't give an absolute right to determine that a soul is in fact in Hell. Not in an absolute sense. I could be wrong, of course.