Expert says he's 99.9 % sure Karr's handwriting matches ransom note!
Veteran of Misadventures
If I am not mistaken, I seem to recall at the time of JonBonet's murder they obtained semen samples from her body. If that is the case that DNA evidence is going to be a lot more compelling than a handwriting exemplar. I really think this is basically just a guy who is using the media to tout his expert witnessing skills. It likely will be some evidence but not the best evidence if Karr's semen is a match with the semen they found on JonBonet.
there apparently were also 2 blood stains recovered, one from JB's underpants and the other from somewhere else I can't quite remember where. There was also a fingerprint on JB's underpants, but I believe it's only a partial print, and Dr Lee says it could come from some person working for the manufacturer who left a print while making the garment. In any case, as you've stated, EB, it's most likely gonna come down to forensics, ie. DNA. If they can't place Karr at the murder scene, I don't think they can convict him based solely on his crazy confession...