There is no statute of limitations on murder.
It wouldn't fall under double jeapardy because they aren't the same charge.
BUT Florida law says you cannot be charged multiple times for crimes relating to the same incident. Caylee missing is the crux of these charges, if they go to trial on the neglect charges and have not filed the murder charge they cannot go back and charge her again. In normal situations this is to stop abuse by the prosecuters office of ruining your life by charging you in dribs and drabbles of charges.
In this case, which I don't see happening, but if they cannot file the murder charges before the neglect charges go to court it will have been a major strategic error by LE. Of course they expected her to talk when they hauled her into jail and saw it as the quickest way to find Caylee if she was still alive. But Baez is hoping and praying they get to the November neglect trial before a murder indictment can come down.
http://www.wftv.com/news/17193405/detail.html?rss=orlc&psp=news
LOOPHOLE COULD ALLOW CASEY TO BEAT SYSTEM
A loophole could allow Caylee Anthony's mother to beat the system. She's still only facing charges of child neglect and giving false statements.
If her attorney asks for a speedy trial, they could be the only charges she ever faces. Florida law prohibits a person from being tried on more serious charges at a later date if the person stands trial for something that's related.
"If you lose a kid and that results in a child's death, that's one and the same case, because those are manslaughter charges," said board-certified trial attorney Richard Hornsby.
If Casey was found guilty of child neglect, she would only serve up to five years in prison versus a maximum of life for murder. Still, detectives have never said that Caylee Anthony is dead or that Casey is under investigation for murder or manslaughter.