Mischa Barton: I'm Responsible for DUI

By Nicholas White

01/10/2008 at 12:50 PM EST

Mischa Barton is speaking out for the first time since her DUI arrest last month.

"Obviously I'm 100 percent responsible for my actions in this case," Barton, 21, told Ryan Seacrest's L.A. radio show Thursday morning, about her DUI arrest. "I'm really disappointed in myself. I don't know what to say about it, except that I'm not perfect, and I just don't ever intend to do something this stupid again."

The former O.C. actress was arrested for DUI in L.A. early the morning of Dec. 27.

"I was out with some friends and actually hadn't been driving earlier in the night, but I wanted to get my car home." Barton explained. "I can't really get into specifics. We've got the case coming up, and I'm not supposed to say anything about what happened. I was pulled over."

Barton, who was also cited for not having a valid license when she was pulled over, added: "I didn't have a license. I grew up in New York, the land of people who don't have to drive. It's always been the toughest thing about living in L.A. for me. I usually try not to get behind the wheel."

Barton's next film, Assassination of a High School President, costarring Bruce Willis, premieres at the Sundance Film Festival later this month.