ORLANDO (CBS4) – Casey Anthony’s mother will not face perjury charges for changing her testimony on the stand.

Cindy Anthony initially told police she did not search for chloroform on the family computer.  During the trial, however, she stunned prosecutors when she testified that she did indeed do searches for chloroform on their home computer.

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Prosecutors believed, along with sheriff’s investigators, that Casey Anthony had performed the search as she plotted to kill Caylee.

Later, testimony by two of Cindy Anthony’s co-workers that the company’s electronic records showed that she was logged into her work system for most of the day on both March 17 and March 21 when the chloroform searches were done.

Cindy Anthony said she had performed the internet searches for chloroform while looking up information on chlorophyll, a green pigment found in plants. Chloroform is a chemical that can be used as a sedative and is fatal to children in small doses.

A co-worker said the system would not have recorded Cindy Anthony’s presence if a person hadn’t been actively using the work computer.

During a news conference on Tuesday, Orange County Sheriff Jerry Demings said they are looking into an allegation of witness tampering.  The sheriff held the news conference to defend his investigation and because his office had been besieged with interview requests since the verdict.

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“The ultimate goal … is that our personnel can get back to work doing the business of the taxpayers and residents of Orange County,” Demings said. “This is the only way that we can move forward.”

Demings said his office followed up on more than 600 tips and worked with more than 100 FBI agents. He said he is still in the process of working with his accounting department to total up substantial investigative costs. Prosecutors want Anthony to incur those costs because they said the lies she was convicted of telling investigators directly led to the expenditures.

“Obviously those were resources that could have been put toward finding other missing children,” Allen said.

Texas Equusearch, the private group that conducted several searches for Caylee in 2008, filed a lawsuit against Anthony on Tuesday, seeking damages for what it spent on searches. The lawsuit claimed Anthony made misrepresentations to the group’s founder, causing extensive, costly and time-consuming searches for Caylee.

Last week a jury acquitted Casey Anthony of murder in the death of her 2-year-old daughter Caylee. She was, however, found guilty of lying to law enforcement.

Casey Anthony is scheduled to be released from jail this Sunday.

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