It's been 11 years since Casey Anthony was acquitted of murdering her daughter in a court case that garnered international attention reminiscent of the media frenzy that surrounded the O.J.

"Pathological lying isn't just, 'I'm lying a lot because I don't want to be in trouble.' They can lie about things that have little consequence to them and make up things for reasons that aren't clear," says Tracey Marks, a general and forensic psychiatrist with over 20 years of experience.

Anthony maintains her innocence throughout the course of "Casey Anthony: Where the Truth Lies," stating she is a "convicted liar" but not a killer.

Why believe convicted liar Casey Anthony: Documentary director addresses 'understandable' outrage.

In fact, most pathological liars aren't good liars, she says, because they "don't consider the consequences or repercussions.".

"They don't say, 'Oh, I shouldn't do this because someone will know I'm lying and catch me.' It's more a force of habit and something they're conditioned to do in-the-moment without thinking about it.".

Like any behavioral habit, it's hard for pathological liars to overcome an impulse

"People can overcome pathological lying," she says, "but only if they actually want to."