I've never heard of non-original letters being admitted as evidence. These days they could have been created in numerous ways. Maybe the law is different in Arizona but that whole letter thing sounded crazy to me.
In my experience authentication of handwriting requires the original for a number of reasons:
http://www.photorestorics.com/article-316.html
In a case like this where suddenly discovered, non-original letters are found by the defendant or her former lovers, I'm not seeing a big problem in not admitting them as evidence.
Just sayin', it's an issue that'll be raised on appeal and Juan's perjury threat will be a big part of it. Idk whether matt had the originals or not, but a threat of a perjury charge "before your feet hit the ground" definitely implicates a constitutionally appealable issue. When coupled with Nurmi's statement about what the expert concluded and the fact that Jodi was representing herself at the time -- I think that handwriting's on the wall. I had an inkling when I first heard about the hearings on the letters and posted about it. Then I heard Nurmi say, with no objection, that one of them was determined by an expert to be "probably" written by Travis. It'll be one of the best grounds for appeal they have. jmo.