An attorney for Mischa Barton entered a plea of no contest in her DUI case Thursday in a Beverly Hills courthouse.

Barton, 22, did not attend the hearing.

The former O.C. star was put on three years' probation, ordered to attend a three-month alcohol education program and fined $1,652.

As part of her plea, the marijuana possession charges were dropped.

Barton was charged with DUI, possession of marijuana and driving without a license in February after an arrest in West Hollywood last December.