(CNN) - Casey Anthony's defense attorneys are seeking to question a convicted felon who served prison time for kidnapping, claiming in court documents he is linked to Anthony's father through cell phone records.
Vasco Thompson, 52, is on an amended witness list filed Tuesday in Anthony's capital murder trial. Orange County Chief Judge Belvin Perry Jr. has not yet ruled on whether Thompson can be deposed or testify in the trial.
Casey Anthony's father, George Anthony, denied knowing Thompson or ever speaking to him in a statement released by his attorney.
Prosecutors allege that Casey Anthony, 25, killed her 2-year-old daughter Caylee in 2008 by using chloroform on her and putting duct tape over her nose and mouth. They allege she then put the little girl's body in black garbage bags and stored it in her trunk before dumping it in woods near her home.
Caylee's skeletal remains were found December 11, 2008. She was last seen June 16, 2008, but her disappearance was not reported until July 15, 2008, after Anthony's mother, Cindy Anthony, demanded answers from her daughter about Caylee's whereabouts.
Anthony faces seven counts in Caylee's death, including first-degree murder, aggravated child abuse and misleading investigators. If convicted, she could face the death penalty. She has pleaded not guilty.
"Mr. Thompson is a recently discovered witness through the ongoing efforts of defense investigators," according to the court documents filed Tuesday. "This witness was connected to George Anthony through his cell phone records."
A background check revealed that Thompson "has a violent criminal history and has served a 10-year prison sentence for kidnapping," according to the court documents.
"Because of the recently discovered and unexplained relationship between George Anthony and Vasco Thompson, their finite contact which, based on cell records, existed only during the relevant time period, and Mr. Thompson's violent criminal history, good cause is shown for the late disclosure of this witness," the defense says in the filing.
Those contacts, they allege, included four contacts on July 14, 2008 - the day before Caylee was reported missing by Cindy Anthony.
The defense said it needs to question Thompson "to determine the existence of relevant admissible evidence in this trial."
Thompson refused to speak with defense investigators and called police when he was questioned, the documents said.
"Mr. Anthony does not know Vasco Dagama Thompson," the Anthonys' attorney, Mark Lippman, said in a statement. "Mr. Anthony does not recall ever speaking with Mr. Vasco Dagama Thompson at any time including July 14, 2008, by any form of communication."
Lippman pointed out the defense has failed to identify who initiated the calls or the length of time of each telephone call.
"This simply appears to be another attempt by the defense to attack my client," Lippman said. "Mr. Anthony has and will continue to maintain the position that he had nothing to do with the death of Caylee Marie Anthony or any of the events that occurred afterward regarding the actions of the defendant Casey Anthony established by the state of Florida in the presentation of their case."
According to records attached to the amended witness list, Thompson was sentenced in 1998 to 40 years in prison for kidnapping. He was required to serve eight years in prison and 30 years on probation. The Florida Department of Corrections website shows he was in and out of custody but was released in 2004.
It was unclear how Thompson might fit into the defense's strategy in the Anthony case.
Prosecutors rested their case earlier Wednesday, and Perry rejected a defense request for a judgment of acquittal, saying the jury must decide what to make of the evidence.
Casey Anthony's defense attorneys will begin presenting their case Thursday. The trial, held in Orlando, is in its fourth week.
The defense has said Caylee was not killed, but rather drowned in the family pool on June 16.FULL STORY
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