I mean, this question is not just about normal criminals.
Think like very bad crimes. Like serial killers, rapists, child rapists, terrorists, corrupt officials, terrible leaders, cruel dictators, generals that ignore laws of war, or like people has bad as Hitler. Which of these people do you think deserve a respectful burial, if any.
Is there a level of evilness that you think should not be allowed to have a proper buriel or have their corpses mutilated. Or should everyone deserve a respectful burial regardless of crimes.
I personally don’t even know how to answer this question myself. Like the funeral isn’t even for the dead. Its for the living. So to me, the question seems like, should the relatives of a bad person be allowed to see the corpse treated respectfully. I personally don’t have an answer to this question.
This says more about you than humanity as a whole.
I’ll bite, what does it say about me?
If you think people will do X, that means you think you would do X.
I would do X too if I was in the same situation, with the same genes, and the same upbringing, and same circumstances, and same influences, and same traumas, and same biases.
Same genes? If your argument is that physics dictates reality, then sure whatever. But you wouldn’t be you. You would be them.
My point is that, if you get to be YOU, but with all the same external stimuli, then people would choose to do different things.