Just seen Black-Winged Redbird - and I reckon its Brett Partridge - the Forensics guy...
Theory - he was there in episode 1. (screen-writers delight!)
Who says he's dead? If he can get into the CBI and burn people alive, if he can get people to kill themselves on a whim, etc - he can certainly create a make-believe death.
Was he really killed? I wonder!
Also - when Jane gets the telephone message regarding Lisbon - it sounds exactly the same as Brett Partridge!
If you had created a list of x people, and you were one of those people - bump yourself off the list and the pressures off!
Of course - there are probably many people involved, but I still think there's one guy heading it all up. Also as a forensics guy, he'd be doing "his thing". People invariably tend to do what they're into - and even as a character, he'd be "doing" what he's "good at"/"enjoys". Someone that enjoys cutting up bodies, enjoys the macabre, etc isn't really going to be sitting behind a desk - they're going to be in an environment where they can continue to experience that (distorted) "delight".
He's also, therefore, going know about evidence, he'd know about not leaving evidence/a trace of himself.
He is also very anti-Jane, and Jane has had a run in or two with him.
Theories that say it's Jane or Lisbon are blown out of the water by the recording made by Jane's psychotherapist - (a) it was a man she saw (b) it clearly wasn't Jane (though possible that she had her head messed with 'NLP stylee') - but then Jane would have been aware of the records being transcribed and would have most likely gotten rid of those as well as the records she kept and the records with the University.
Just a thought :) ( <<OMG! Is that a smiley :S )
