Culkin, star of the "Home Alone" films, was arrested Sept. 17 after police stopped a car in which he was a passenger. Officers found over a half-ounce of marijuana and several tablets of Xanax, a prescription medication used to treat depression and panic disorders, court records show.
He was given one-year deferred sentences on each of the charges and was assessed $540 in fees.
Assistant District Attorney Greg Mashburn said Culkin had completed all requirements of his probation before coming to court, including passing a drug and alcohol assessment.
"This was a rare circumstance for Mr. Culkin," Mashburn said. "He was not an abuser."
Culkin, 24, arrived in court about 10 minutes before his case, wearing a gray suit and a white open-collared shirt. He made no audible comments.
He testified recently in the