that sounds like double jeopardy...you usually cant be re-tried for a crime unless it's an appeal, in which case your sentence can never go up. it can stay the same or be reduced, but it cant go up.
im not going to get into the nitty gritty here but it just sounds unrealistic. but im not going to go yes or no on this deal...im in law school, this is interesting and im going to ask about it, itd be kinda cool if psychos were doing this to get the death penalty in order to escape life sentences. ill let you know if i find something definitive.
but shit, all they gotta do to escape a life sentence is try to rob from me...hehehe.