'America’s most hated mum' speaks for the first time about her daughter's murder case.

On July 5, 2011, a jury found Casey Anthony not guilty of the murder of her two-year-old daughter, Caylee.

During the six-week long trial – described by Time magazine as the ‘social media trial of the century’ – Casey was branded the “most hated mum in America”.

The not-guilty verdict was met with public outrage and many still believe Casey is responsible for her daughter’s death.

Now, nine years on, Casey Anthony has spoken to the press for the first time.

In an exclusive interview with the Associated Press, 30-year-old Anthony said she believes her daughter – who would be 12 were she still alive – would be a “total badass”.

"I'd like to think she'd be listening to classic rock, playing sports," she said.

Casey said she is still not certain about the events that led to her daughter's death.

"I'm still not even certain as I stand here today about what happened," she said.

"Based off what was in the media...I understand the reasons people feel about me. I understand why people have the opinions that they do."

At the same time, Casey said she doesn't "give a s***" about people's opinions of her.

"I never will. I'm OK with myself, I sleep pretty good at night," she said.

Caylee was last reported seen on June 16, 2006. Thirty-one days later, her maternal grandmother, Cindy Anthony, reported her missing.

She told authorities that Casey's car also smelled like a "dead body had been inside it".

When Casey was arrested a day later on charges of child neglect, she told police that Caylee had been kidnapped by her nanny.

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She was charged with first-degree murder in October 2008.

Two months later, Caylee's remains were found with a blanket inside a garbage bag near the family home. Duct tape was found, with medical examiners reasoning it had been used to kill the two-year-old girl.

Anthony's defense attorney suggested that Caylee had drowned, and that the girl's father had covered up her death.

It took the jury less than 11 hours to find Casey Anthony not guilty of first-degree murder, aggravated manslaughter and aggravated child abuse.

ONLY ON AP: Casey Anthony tells reporter @Joshrepp about her daughter, life since acquittal & challenges she faces. https://t.co/jhaDkWajHO pic.twitter.com/MDgvKFiLgm

— AP South U.S. Region (@APSouthRegion) March 7, 2017

When asked about the trial, or the circumstances of her daughter's murder, Casey said, "Everyone has their theories".

Just last week, former Circuit Judge Belvin Perry Jr., who presided over Anthony's trial, said there was a possibility that she had accidentally killed her own daughter.

"There was a possibility that she may have utilised [chloroform] to keep the baby quiet...and just used too much of it, and the baby died," he told the Orlando Sentinel.

"That’s just one of the many theories as to how this beautiful young lady [Caylee] tragically met her death...The only person that really knows what happened was Casey.

“For whatever reason, people are still fascinated with Casey Anthony," he said.

But Casey told the Associated Press she has no explanation for what happened to Caylee.

"As I stand here today I can't tell you one way or another," she said.

"The last time I saw my daughter I believed she was alive and was going to be OK, and that's what was told to me."