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During her interview this morning on the popular KIIS-FM radio show "On Air With RYAN SEACREST", former "O.C." actress MISCHA BARTON opened up for the first time about her December arrest for suspicion of DUI.

"I'm 100 percent responsible for my actions in this case and I'm really disappointed in myself," she told Ryan. "I don't know what to say about it except that I'm not perfect and I don't ever intend to do anything this stupid again."

Mischa tells Ryan what went down that night. "I was out with some friends, and I hadn't been driving [earlier] in the night but I wanted to get my car home, so I decided to drive home," she said. "I can't really get into specifics because we have the case coming up and I'm not supposed to say anything about what happened. But yeah, I was pulled over."

She goes on to talk about the fact that she was driving without a license. "I didn't have a license," she said. "I grew up in New York, the land of people who don't have to drive. It's always the toughest thing about living in L.A. for me and I usually try to not get behind the wheel."