As the defense unrolls its case, key questions linger -- and legal experts say the jury could acquit if they don't get answers

For the first time since being acquitted in 2011 in the death of her 2-year-old daughter, Caylee, Casey Anthony spoke out in an interview with the Associated Press.

“I’m okay with myself, I sleep pretty good at night,” the 30-year-old, once dubbed “the most hated mom in America,” said, adding that she feels a kinship with O.J. Simpson.

PEOPLE began covering the case the day after Caylee was reported missing, interviewing more than 200 key players in the case. Here is PEOPLE’s cover story from July 4, 2011, just days before the shocking verdict.

For three intense weeks, George and Cindy Anthony alternately listened and testified as the State of Florida methodically laid out a first-degree-murder case against their daughter Casey: Hair samples. Air samples. Damning computer searches for the words “chloroform” and “neck breaking.” A climactic star turn by Orange County chief medical examiner Dr. Jan Garavaglia—a.k.a. “Dr. G” of the hit Discovery Health Channel series—who looked squarely at the jury of seven women and five men and told them in no uncertain terms that Casey‘s 2-year-old daughter Caylee had been murdered: “There is no other logical conclusion.” Having heard the state’s case, do the parents who stood by her for three years before subtly pulling back as the trial began now believe their daughter is guilty? “Honestly, I think they’re all over the place with that,” says a family friend. “What they want, and what they’ve always wanted, is to know what happened.”

PEOPLE cover, July 4, 2011

It’s a desire shared by the millions of trial watchers who have become hooked on the twisty case, along with the spectators who line up daily for a chance to see the drama and its key players up close. Message boards are flooded with angry posts calling for Casey‘s conviction. Meanwhile the 25-year-old defendant has displayed everything from scowls to sobs to stone-faced indifference as she sits beneath the words emblazoned high in the courtroom: Equal Justice Under The Law. Yet despite riveting testimony from more than 30 witnesses and 315 pieces submitted into evidence, the mystery surrounding Caylee Marie Anthony‘s disappearance on June 16, 2008, largely remains as vexing as ever. Among the unanswered questions when prosecutors rested their case in a tension-filled Orlando courtroom on June 15: When exactly did Caylee die? Where did she die? If, as the state claims, she was murdered by her mother—why? And perhaps the most surprising question of all: Could Casey Anthony possibly the most hated woman in America right now—possibly go free?

Quite simply: yes. “This is definitely not a slam-dunk case,” says Karin Moore, a former criminal-defense attorney and law professor at Florida A&M University. “The state doesn’t have an eyewitness. They don’t have a confession, so most of the evidence is circumstantial.” An acquittal—or a conviction on a lesser charge—is hardly far-fetched. “There are gaps in the prosecution’s theories, and the jury will notice them,” says New York City defense attorney Stuart Slotnick. A prosecution source counters that the evidence against Casey is substantial and sufficient. “People hear ‘circumstantial’ and think that means it’s a weak case,” the source says of the evidence, which ranges from the location of Caylee’s remains to duct tape placed over her nose and mouth (see page 53). “But what it means is that we built a case using a lot of evidence. There is no one smoking gun.”

Casey Anthony
| Credit: Getty

The jury may not see it that way. Sequestered and cut off from friends, family and all media coverage of the case, “there’s an enormous amount of pressure on them,” says Dr. Philip K. Anthony, a top trial consultant. Seated some 15 feet directly across the artificially lit courtroom from the defendant six days a week, “they’re quizzical about Casey herself,” he says. “She’s fairly poised when she needs to be and emotional when she needs to be. They’re probably very interested in that.” Confined to a solitary cell in prison (see box), she commands the spotlight in court: On June 14, she riveted onlookers when she pointedly looked away after her mother mouthed “I love you” upon leaving the stand. “She does love Casey,” the Anthony family friend says of Cindy. “Casey is her daughter. Both George and Cindy love her unconditionally.”

Yet they both listened as defense attorney Jose Baez stunned the courtroom in his opening arguments with claims—yet to be solidified—that Caylee accidentally drowned in the family swimming pool and that Casey‘s father, George, had helped cover up the death after years of sexually abusing Casey. (George has denied both claims.) Now that the defense is under way, the jury will be paying close attention to whether those bombshells are backed up with hard evidence. “Baez made a promise: ‘You’re going to hear that Casey was sexually abused,'” says assistant state attorney Stacey Honowitz. “Now the defense is in a situation where they have to prove something.”

Of course, the burden of proof rests with the prosecution, not the defense. And the multitude of photos showing a fun-loving Casey partying in the weeks following Caylee’s disappearance may not be enough to establish a motive for the murder—or that Casey had planned it in advance. “Party pictures can prove that she was out partying later but not that she intentionally killed [her daughter],” says Karin Moore. Nor is the wealth of testimony exposing Casey‘s astonishing web of lies—including the 30 days she kept Caylee’s disappearance a secret—surefire proof that she killed her daughter. “Being a liar does not mean she’s a murderer,” says Slotnick. “It means she’s an unlikable liar.” Still, should Casey be called to testify by the defense—something experts say is necessary to beef up her claim of sexual abuse—”her credibility has already been attacked,” says Moore. “If she decides to testify, that will hurt her.”

Caylee Anthony
| Credit: Courtesy Anthony family

Regardless of whether Casey testifies, the prosecution source says the state is confident she will not walk away a free woman. “The evidence is there,” says the source. “Her actions are there. Her own words are there. I don’t like to look at it like ‘win’ or ‘lose,’ because, as the judge says, this is not just a game. I believe we have a solid case.”

Ultimately, of course, the decision rests with the five men and seven women seated attentively—and most often impassively—in the jury box who must agree unanimously on a verdict. “No one knows what the jurors are going to do, in part because the jurors themselves don’t know,” says Dr. Philip K. Anthony. “They are looking over at Casey and trying to figure out: ‘Who is she?'” As with the other perplexing questions surrounding CaseyAnthony, the answer remains, for now, stubbornly out of reach.