Trino said:If Karr murdered JB, why write a kidnapping note, complete with practice sheets? It would seem he would be so horrified about JB's "accidental" death, that he would exit the house ASAP. It's doubtful Karr would have written the note before his encounter with JB, since if his motive was kidnapping, why didn't he kidnap her? I agree that someone who breaks and enters wants to get away ASAP.
He may have written the note beforehand, fully intending to complete the kidnapping. If the kidnapping went wrong and she 'accidentally died', the note had already been written and perhaps even already taped to the staircase.
I watched an interview posted by Linda7NJ of a woman who says that JK confessed the crime to her after a night of drinking five years ago. She wasn't the textbook definition of a reliable witness, but the quickness with which she related the story and the details she included were somehow a bit convincing to me and (at the very least) made me think. She claimed that JK had snuck into the house while the Ramseys were at the Xmas party that night and hid under the guest room bed across from JonBenet's room (I think that would be John Andrew's bedroom). Here's the link to that video--it's worth watching: http://websleuths.com/forums/showthread.php?t=42189&highlight=confession