Video: Prosecution rests in Casey Anthony trial

updated 6/15/2011 3:35:21 PM ET 2011-06-15T19:35:21

Prosecutors spent 19 days proving beyond any doubt that Casey Anthony is a liar who loves to party. But did they also prove that she murdered her 2-year-old daughter Caylee?

The prosecution rested its case Wednesday after introducing a wealth of circumstantial and forensic evidence that they say shows that the young single mother suffocated her daughter by wrapping duct tape around her head. They say she left the girl's body in her car until it stank and then dumped it in the woods near the home she shared with her parents.

But there are holes. They have no witnesses who saw the killing. No one saw Anthony with the body. And because the body was so decomposed, there is no absolute proof that the child was suffocated, just the tape remnants on her skull. Caylee's remains were found in December 2008, six months after the girl was last seen.

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And while the prosecution used Anthony's friends, parents and brother to show that she lied repeatedly before and after her child died, the witnesses also all agreed that she was a loving and doting mother. If convicted of first-degree murder, Anthony faces a possible death sentence.

"I think (the prosecutors) did as best they could with the evidence that they have," said Leslie Garfield, a criminal law professor at Pace Law School in New York. "The problem is that all 12 jurors have to find a verdict unanimously beyond all reasonable doubt. So you wind up having a pretty heavy burden."

And that's what Anthony's attorneys will bank on when they begin their case Thursday — but they also set a high bar for themselves. In his opening statement, lead defense attorney Jose Baez said he will show that Caylee accidentally drowned in her grandparents' above-ground swimming pool and that Casey freaked out. He said Anthony's father, a former police officer, made the death look like a murder and helped her dump the body. George Anthony adamantly denied the claim during his testimony, along with an accusation that he molested Casey as a child.

If the defense has no witnesses to back up their claims of a drowning and cover-up, many lawyers familiar with the case think Anthony, 25, will have to testify in her own defense, opening her up scathing cross-examination.

"That's really risky," Garfield said.

In her opening statement, lead prosecutor Linda Drane Burdick didn't hide the central mystery of the case: "What happened to Caylee Marie Anthony?"

She and her assistants then methodically tried to answer that question, showing that Anthony had been living the life of a party girl before Caylee disappeared in June 2008 — and didn't slow down until she was arrested weeks later.

They showed that Anthony, then 22, lied to her parents and detectives about working as a party planner at Universal Studios theme park. She also maintained that a nanny named Zanny had taken the child in several conversations with investigators — a vastly different explanation from the drowning story the defense is now using.

Prosecutors showed that in the days after Caylee was last seen — the period when prosecutors say she was murdered — Anthony hid from her parents, spent time with her boyfriend, went shopping and hung out with friends.

When her parents and brother visited her in jail after her arrest, she insisted she had no idea where Caylee could be.

"Her conduct just sticks out," said Karin Moore, an assistant professor at Florida A&M College of Law. "If she knew her child had died or was missing, she was not acting like a grieving mother. It may be enough for a jury to convict her."

Still, Moore says it's risky for prosecutors to rely so heavily on bad character evidence.

"They're asking a jury to decide, 'She's a bad person, so she must have killed the child.' I think that's a big leap for a jury to have to make," Moore said.

Prosecutors used forensic evidence to bolster the case, primarily from Anthony's car and Caylee's remains.

Shortly after their daughter and granddaughter disappeared in June 2008, Casey's parents got a notice that their daughter's car had been towed and needed to be claimed. George Anthony and the tow lot operator both said the Pontiac Sunfire smelled like death.

Prosecutors played a tape of a frantic 911 call made by Anthony's mother, Cindy, reporting her granddaughter missing. Jurors took notes as they watched the grieving grandmother drop her head in tears while listening to the recording in which she said: "It smells like there's been a dead body in the damn car."

That smell is a major component of the prosecution's case.

They called Arpad Vass, a senior researcher at the Oak Ridge National Laboratory in Tennessee, who offered what's arguably the most controversial evidence so far. Vass and a colleague used a syringe to extract air from a can holding a carpet sample from the Pontiac, then injected the air into a special instrument to identify the substances it contained.

The substances were compared against a database of more than 400 chemical compounds Vass has previously identified from the decomposition of bodies. He backed up the prosecutors' theory, testifying that he smelled an "overwhelmingly strong" odor of human decomposition in the air sample and that his machine found high levels of chemical compounds observed when the body breaks down, such as chloroform.

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But Anthony's attorneys say the stench came from a bag of trash left in the trunk during the broiling Florida summer. They argue that Vass' tests haven't been duplicated elsewhere and that the researcher has refused to share his database, claiming it is proprietary.

Prosecution experts also said a single strand of hair found in the car's trunk showed signs of decomposition. But not all the forensic scientists agree on the level of decomposition.

"I do have issues with the validity and reliability of the odor testing because the doctor relied on his own studies," Moore said. "It was not peer-reviewed."

Still, Garfield said disagreements in the testimony of expert witnesses may not necessarily cause the jury to dismiss the evidence.

"On one hand, it doesn't look like a rock-solid case for the prosecution," Garfield said. "But on the other hand, it looks more real. If you have too many witnesses saying exactly the same thing, then a jury could be cynical. If they conflict a little bit, then you could say it's not a rock-solid story, but you can also say these people are real — let me look at the whole picture."

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