Despite the evidence against Anthony, though, some questions remain. Namely, could she go free?
As the defense begins, PEOPLE looks at the strengths and weaknesses of the prosecution's case.
Strengths Computer Searches: One of the most damning pieces of evidence against Anthony has always been the searches on the family computer, which included, "how to make chloroform," "neck-breaking" and "inhalation."
The prosecution scored big while interviewing computer expert John Bradley on June 9. After establishing that chloroform residue was found in Anthony's car, the prosecution had Bradley testify that Anthony visited a website about chloroform.
"How many times was that site visited?" asked the prosecutor.
"According to the history," Bradley answered. "84 times."
As people in the gallery gasped, every juror jotted down notes.
Casey's Own Words: Although Anthony has not testified, the prosecution entered videos of jailhouse visits into evidence. During these visits, taped shortly after her 2008 arrest, Anthony had kind words for her father, George. "You've been a great dad and the best grandfather," she told him. "Don't for a second think otherwise."
The jailhouse tapes seemingly contradict the defense's claim that George sexually molested Casey. "Her own words came back to haunt her," a prosecution source tells PEOPLE. "It was very effective."
Partying Pictures: Four days after Caylee Anthony disappeared – and the defense claims that she accidentally drowned – Casey Anthony participated in a hot body contest at an Orlando club. Prosecutors introduced photos of a happy-looking Anthony partying, smiling with her boyfriend, drinking and grinding against another girl.
The jury, normally expressionless during the trial, watched carefully. Some of the older female jurors shook their heads and sighed.
Weaknesses Cause of Death: It's the biggest mystery of the case: how exactly did Caylee die?
"It is our position that ... Caylee Marie Anthony died as a result of three pieces of duct tape applied to her nose and mouth, as a result of poisoning by chloroform [and] as a result of a combination of the two," Assistant State Attorney Linda Drane Burdick said in court on June 15.
Not so, says the defense: "Caylee Marie Anthony drowned in the pool," defense attorney Jose Baez said in opening arguments. "It was a tragic accident."
"Drowning is a reasonable explanation," says Orlando criminal defense attorney Richard Hornsby. "And there is no physical evidence to dispute it."
The Hair in the Trunk: It was just a single strand of hair – consistent with Caylee and showing signs of decomposition. Although the state believes it proved that Caylee's dead body had been in the trunk, the defense questions the scientific findings.
"This is junk science," Baez has said. "And it's just one hair."
Prosecutors admitted that there was less physical evidence in the trunk than they had expected, but speculate that Anthony may have attempted to clean the trunk. "In this case," the prosecution source says, "we believe one hair is sufficient."
Baez and his co-counsel begin presenting the defense on Thursday morning. After he finishes – in as few as five days or as long as five weeks – the prosecution will have one last chance to introduce new witnesses.