I would be surprised if that passed federal rule of evidence 404(a), which is a part of U.S. law which says "Evidence of a person’s character or character trait is not admissible to prove that on a particular occasion the person acted in accordance with the character or trait."

I mean, this is assuming that we're talking about "years later" -- in other words you really are trying to say "this person was of a very morbid character and was interested in researching facts about human body decomposition." Heck, I made searches like that when I was writing the first draft of a NaNoWriMo novel.