Actress Mischa Barton, facing a drunk driving sentence, will avoid jail time by accepting a plea deal, according to reports.

The 22-year-old best known for her role in TV series 'The O.C.', will agree to an unsupervised probation term of three years at her arraignment in a Beverley Hills court on Thursday. She will plead no contest to DUI, a source told People magazine.

The actress will also pay a fine of $1700 and be sentenced to attend an alcohol education class for three months.

Barton was pulled over in Los Angeles on 27 December and arrested for drunk driving after police spotted her weaving between lanes of traffic and failing to indicate when making a turn. Sheriff deputies discovered marijuana in her possession and found had no licence.

"Obviously I'm 100 percent responsible for my actions in this case," Barton told DJ Ryan Seacrest in January. "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."

In terms of the plea deal, the drug possession charge will be dropped due to the small amount found, while the charge of driving without a licence will be reduced to an infraction.

The deal is expected to be finalised by the court on Thursday.