Two-year-old Caylee Anthony was not murdered by her mother as prosecutors maintain, but drowned in the family's pool in June 2008, Casey Anthony's defense attorney told jurors during opening statements Tuesday.

Casey Anthony and her father, George Anthony, panicked upon finding the child, Jose Baez said. Anthony found her father cradling Caylee's body the morning of June 16, 2008, he said, and George Anthony yelled at his daughter, "Look what you've done. Your mother will never forgive you." He told her she would go to jail for child neglect, Baez said.

"This is a tragedy that snowballed out of control," Baez said. "This is not a murder case. This is not a manslaughter case ... this is a tragic accident that happened to some very disturbed people."

Anthony is accused of killing Caylee in 2008 and lying about it to investigators. The Orlando trial, which comes after nearly three years of legal twists, turns and delays, has garnered interest nationwide.

Anthony has pleaded not guilty, and denies harming her daughter or having anything to do with her disappearance. Baez has said that once all the facts are known, it will become clear his client is innocent.

In addition to capital murder, Anthony faces six other charges, including aggravated child abuse, aggravated manslaughter of a child and providing false information to authorities. If she is convicted by jurors -- seven women and five men along with five alternates -- she could face the death penalty.

Baez dropped another bombshell when explaining Anthony's behavior in the month before Caylee was reported missing on July 15 -- partying and lying about the child's whereabouts. "Casey did what she's been doing all her life, or most of it: hiding her pain," he said, adding that Casey Anthony had been sexually abused by her father starting at age 8.

Anthony was taught from an early age to behave as if nothing was wrong, he said, describing an incident where she went to school and behaved normally at age 13 after performing oral sex on her father. George Anthony sat stone-faced in the gallery as Baez made the allegations; Anthony put her head on the shoulder of another defense attorney and sobbed.

However, in his testimony, George Anthony -- the trial's first witness -- denied ever sexually abusing his daughter. He also said he was not at his home when Caylee died. "If I'd have known something happened to Caylee, we wouldn't be here today," he said as Casey Anthony shook her head.

George Anthony said as a former police officer, he was trained in CPR and that he would have done everything possible to save his granddaughter's life if he had found her in the pool as Baez alleged.

Baez also alleged Casey Anthony was inappropriately touched by her brother, Lee, although "it didn't go as far" as it had with her father. It was bad enough, however, he said, that the FBI conducted a paternity test to see if Lee Anthony had fathered Caylee.

He told jurors the Anthony family "keeps its secrets quiet ... You're going to hear all kinds of bizarre family behavior."

Baez said the family was "religious" about removing the above-ground pool ladder so that Caylee, who loved to swim, had no access to it. He suggested that Caylee's grandmother, Cindy Anthony, had forgotten to put it up the night before Caylee drowned, as she and Caylee were just exiting the pool when Anthony arrived home.

The day after Caylee's death, June 17, Cindy Anthony told coworkers she believed someone had been swimming in her pool, as the gate was left open and the ladder was left in place, Baez said.

Baez attacked much of the state's forensic evidence, saying such evidence has never before been admitted into courts -- and a death-penalty trial should not be the test case, as much of it is "questionable."

Police zeroed in on Anthony from the beginning, he said. "This investigation was extremely thorough when it comes to focusing in on Casey, probably the most comprehensive investigation that you will ever come across, and in the history of the state of Florida. It was directed at one person and one person only. The problem with this investigation is, it reached a level of desperation."

During his two-hour opening statement, Baez also cast doubt on Roy Kronk, the meter reader who found Caylee's skeletal remains in December 2008, alleging that he found the remains in an unknown location months earlier and moved them to where they would be found by authorities in an attempt to cash in on the high-profile case. "He thought he had himself a lottery ticket," Baez said.

"You will not be able to trust a thing having to do with Mr. Kronk, because he had control of Caylee's remains, obviously, for several months," Baez said. "Where he found her we do not know. We may never know, because the police never investigated him."

Kronk's attorney, David Evans, denied the allegations in a statement. "To the extent that the defense is stating that Mr. Kronk somehow had possession of and had something to do with the disposition of the remains of Caylee Anthony, those statements are absolutely false," Evans said.

George Anthony's cross-examination by Baez was punctuated by objections from prosecutors, most of them sustained by Orange County Chief Judge Belvin Perry Jr.

Baez did elicit the information that George Anthony did not ask his daughter who had fathered her child until around the time Caylee was born.

George Anthony also said he never asked to meet the fictitious nanny, "Zanny," who Casey Anthony had claimed was named Zenaida Gonzalez. In the early days of the investigation, Casey Anthony initially alleged the woman had kidnapped Caylee, but authorities were never able to find the woman. George Anthony said he had no contact information for "Zanny."

Baez did not ask about sexual abuse, but George Anthony admitted to him he had heard the drowning theory before. Baez also attempted to cast doubt on George Anthony's recall of what Caylee was wearing the day he last saw her, suggesting he would likely not have retained that detail as he didn't know it was the last time he would see her. George Anthony completed his testimony on Tuesday but could be recalled to the stand later.

After Tuesday's court session, an attorney for George and Cindy Anthony issued a statement responding to Baez's claims made during his opening remarks.

"George and Cindy Anthony are shocked and appalled that the Defense would resort to lies about them in today's opening statement. Baez's idle speculation today certainly are not facts, The only result achieved by the Defense in this statement was to further hurt this grieving family, " Orlando attorney Mark Lippman said in the written statement.