Casey Anthony Update: State won't use her jailhouse reaction to discovery of daughter Caylee's remains

(CBS/WKMG) ORLANDO, Fla. - Prosecutors in the upcoming murder trial of Casey Anthony, the young mother who is charged with killing her 2-year-old daughter Caylee in 2008, have decided not to use a secret recording of what they say is Anthony's reaction to the discovery of her daughter's remains months after her disappearance.

PICTURES: Casey and Caylee Anthony, Personal Photos

The decision was announced Monday, just days before scheduled arguments about whether the tape should be allowed in court, according to CBS affiliate WKMG.

Mark O'Mara, a legal analyst for the station, said that while the prosecution has said they won't use the tape as part of the case in chief, it could still be used in the rebuttal phase of the case, after the defense has rested, but O'Mara also said that was probably unlikely.

"I think it was too staged and it could have blown up in their face," O'Mara said, adding its use may have given the defense a valid appeal route.

The recording in question reportedly shows Anthony in a common area of the Orange County Jail on December 8, 2008, watching the news coverage of the discovery of what would later be determined to be Caylee's remains, according to local station WESH.

On the video Anthony can be seen falling into a chair, doubled over and breathing rapidly. Several minutes later, the jail lieutenant noted that Anthony muttered "Oh no," according to WESH.

Anthony's defense attorneys were expected to make the argument that the whole scene was a setup and endangered her chances of getting a fair trial.

Indeed, the video was placed under seal by the court as soon as the state revealed its existence, according to WKMG.

During the same hearing Monday, the state announced it would not call jailhouse snitch Maya Derkovic as a witness in its case in chief. Derkovic, a convicted killer, has claimed Casey told her she used chloroform to knock her daughter out so she could party -- a claim it appears not even prosecutors believe, the station reported.

Finally, prosecutors agreed with the defense that Casey's statements made after her October 2008 arrest should not be admitted in their main case. She had invoked her right to remain silent months earlier after a previous arrest, according to WKMG.

Anthony is jailed on first-degree murder charges. Caylee was 2 years old when she was reported missing by her maternal grandmother in July of 2008.

Anthony has pleaded not guilty and maintains that Caylee was abducted by her babysitter. The trial is scheduled to begin in May.

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