Mischa Barton believes she was slipped a cocktail of drugs a few months ago, which led to her erratic behavior that was caught on tape.
The 31-year-old actress appears on Monday's episode of Dr. Phil and attempts to remember the events that led to her incoherently yelling at neighbors from her backyard. "I think it was complete hallucination," she says. "I have no idea what I was talking about."
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Barton claims the hallucinations were both auditory and visual, and included "specks of light."
The O.C. star adds that she also blacked out and has trouble remembering anything after that. "There's also blackout parts, like, earlier in the night, and then I'll remember my friend saying, 'Please lay down,' and then it'll be gone again," she explains. "And then the whole part outside is just blackout."
In January, ET confirmed that Barton had been hospitalized after Los Angeles police responded to a call for a female that was "yelling and screaming." Upon arrival, deputies located Barton, who was "fully clothed sitting on a coach" and "making incoherent statements." She voluntarily was transported to the hospital, and was released the following day.
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A few months later, Barton claimed at a press conference that she had been recorded by her ex-boyfriend during intimate moments without her knowledge or consent. She tells Dr. Phil that she was a victim of "complete emotional blackmail."
"I couldn’t believe it because I had loved this person and I didn’t think it was possible," she says.
"Were you being threatened with the tape -- ‘Pay me or I am going to sell it?'" Dr. Phil asks. "It is sinister… there’s no way that it wasn’t premeditated," Barton insists.
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In a statement to ET, Barton's attorney, Lisa Bloom, put out a warning to anyone thinking of obtaining or sharing the illegal content. "There is a name for this disgusting conduct: revenge pornography," Bloom said, explaining that the act is "a form of sexual assault, and it is also a crime and a civil wrong in California."
Here's a look at the press conference that Barton held in regard to the alleged sex tape: