The lawsuit alleges that Casey Anthony committed fraud because she knew her 2-year-old daughter was dead and not missing as she and her parents claimed when asking for help from EquuSearch.
"It was Jose Baez's opening statement when he said Caylee was never missing because she had died, that got me really upset," Miller said. "We were lied to and misled."
The group traveled twice to Florida to look for Caylee and spent roughly $112,000, Miller said.
Miller's non-profit group had to turn down 15 other families that asked for assistance in 2008 because they were searching for Caylee, he said.
"We have no agenda other than to recoup the money and use it for which it was intended," he said.
Anthony, who will be in the Orange County Jail for a few more days, will likely be served later today with the latest lawsuit.
Anthony was found not guilty of murdering her daughter by a jury last week. She was found guilty of four misdemeanor counts of lying to police and sentenced to four years. Anthony was given credit for time served and time was shaved from her sentence for good behavior. She is scheduled to be released on Sunday.
This is not the first civil lawsuit Anthony is facing.
A Kissimmee woman named Zenaida Fernandez-Gonzalez is suing Anthony for defamation. Anthony told investigators and her family a nanny with the same name kidnapped Caylee in June 2008. Detectives and Anthony say the nanny is fictitious.
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