This is slightly old news, but I just found a good article that describes the situation, so I figured I'd post it now.
A few months ago, the Supreme Court overturned the murder conviction of Dwayne Giles, ruling that allowing statements from the deceased victim to be used against the accused violates the defendant's right to confront the accuser.
Basically, the Supreme Court is saying that a dead person can't "testify" because he or she cannot be cross-examined. Although the ramifications for this sort of ruling are being questioned for domestic abuse cases, it is great for those of us who believe Mechele should be freed. The ruling sets a precedent saying that evidence such as Leppink's letter to his parents should be inadmissible because he cannot be questioned about it.
If you'd like to read more about the Giles case, go here.