Unless the DNA matches, he won't be convicted. And they're already saying the DNA on JB's panties and under her nails has possibly deteriorated to the point where it's useless. His detailing of the condition of JB's body, what he did to her -- 'gruesome' is used to describe what was done to her...seems to be what convinced the DA that he might be the killer. (Presumably they left those details out of the autopsy.)
There was another break-in a few weeks earlier in a neighborhood not far from the Ramsey's. A man wearing a mask got into a child's bedroom, but the mother heard her scream and scared him away. There was speculation this same man killed JB, and then committed suicide a week or two later. But aside from that, Cyril Wecht, the forensic pathologist with years of experience, says there should've been clues left at the scene, forensics, hair, fiber, etc..(He thinks it was done by a family member or someone they knew well, unfortunately). But another pathologist says what was done to the child was so horrendous that it couldn't have been a rage killing by a parent...because she wet the bed. Patsy's answer to the cops was convincing. "I survived cancer. Do you think I'd lose control and kill my child over a wet bed?" (If the killer is dead, they'll never solve the case.)
Deteriorated? So they didn't run DNA tests at the time and put the results on file? I doubt that.
If Karr's family can prove he couldn't have been in CO the night JBR was killed, then the case against him is over. The lack of DNA will hamper the case, but doesn't necessarily kill it. A handwriting analyst has said that he thinks Karr's handwriting matches the note that was found.
At first, I thought Karr was a celebrity seeker. Now I'm not so sure. I think he's a possibility, but I don't have a strong conviction either way. When I saw John Ramsey's nephew speaking on Fox, I personally thought he looked a lot like Karr. Very creepy. And I heard on Fox this morning that Karr has said he was at a party with his brother where John Ramsey was also in attendence. There must be some linkage there. Lots of rumors, no confirmations. But it is interesting. I hope they grab the perp. The real one.