04/07/2008 at 07:00 PM EDT
will accept a plea deal in her DUI case, sparing her any jail time, a source tells PEOPLE.
The former O.C.
star will plead no contest to DUI at her arraignment Thursday in Beverly Hills court, and agree to serve a three-year unsupervised probation term, the source says.
Barton will also be sentenced to a three-month alcohol-education class, and pay a fine of approximately $1,700.
In addition, a marijuana possession charge against the actress will be dropped, due to the small amount found. Another charge of driving without a license will be reduced to an infraction, according to the source.
A spokeswoman for the Los Angeles District Attorney's Office would not comment on the case.
The terms of the plea deal, negotiated by Barton's lawyer Anthony V. Salerno, are expected to be signed off on by the court Thursday. Such a deal is common for first-time offenders.
Barton, 22, was arrested for DUI
in Los Angeles on Dec. 27, after sheriff deputies spotted her weaving between two lanes of traffic and she failed to signal when making a turn.
On Jan. 10, Barton told Ryan Seacrest's L.A. radio show: "Obviously I'm 100 percent responsible for my actions in this case. 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."