Casey Anthony must take the stand, expert says

During opening statements at Casey Anthony's murder trial in Orlando, Fla., her lawyers stunned the courtroom by claiming her 2-year-old daughter, Caylee, accidentally drowned and that Casey's family covered it up.

"In Session" Correspondent Beth Karas was in court when the bombshell was dropped.

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Co-anchor Erica Hill asked Karas on "The Early Show" if this means Casey Anthony, 25, must take the stand.

Karas said Casey Anthony will have to give her testimony -- because she's the only person who can tell the story the defense is offering.

"The scenario that her lead defense attorney, Jose Baez, painted of the death of Caylee -- her father, George, finding Caylee dead in the swimming pool, as Casey came around the other side of the house in tears, can only be explained by Casey Anthony," she said. "There's no one else."

She added, "George Anthony already testified and denied it, so I do believe we will see her on the stand."

Defense attorneys had planned from the start of the case that Casey Anthony would testify, Karas said.

"There's no known cause of death, because when Caylee's remains were found, she was a skeleton, and her bones were scattered. You couldn't tell how she died. So it's a homicide - no known means. That leaves the defense the opportunity to say, 'Look, if she wasn't killed by her mother, she drowned accidentally,' so it's a good strategy, because no one can say for sure."

The cause of Caylee's death has never been determined..

Another strategy the defense is taking is to admit lies Casey told while she was investigated, Karas said. The goal, Karas said, is to overcome the deceit so jurors will believe the case put before them now.

Karas explained, "The defense has basically admitted that, the 31-day period from Caylee last being seen to being reported missing and tracking Casey's whereabouts, they're saying, 'Basically, we don't contest it. Yes, she lied to her parents, because she grew up in this dysfunctional home. She was molested from the age of 8 by her father and that made her the person that she is and her lies to the police, which are four misdemeanors in the indictment, punishable by one year each, and she's already served three years of that. She's basically admitting that. She'll get on the stand and say, 'Yes, I did it, and here's why.'"

 "So her family is being put on trial -- dysfunction at the home," Karas said. "And the defense already, in the cross-examination of George Anthony, started to raise dysfunction when George Anthony admitted he never asked his 19-year-old unwed pregnant daughter who got her pregnant, for two months. When she was seven months pregnant in a photo, he said, 'I really wasn't sure she was pregnant. I thought it might be water retention because she used to work out and she had stopped running.' It was a little incredulous to many of the spectators in the courtroom."

In his testimony, George Anthony denied that he ever had sexually molested his daughter.

Casey Anthony is charged with first-degree murder. If convicted, she could be sentenced to death.

Prosecutors say Caylee died from duct tape being placed over her mouth and nose. They said during opening statements that all the evidence points to Casey Anthony as the killer.