O'Neal, the 25-year-old son of Ryan O'Neal and the late Farrah Fawcett, was in court Tuesday for his December arrest when he was caught allegedly under the influence and violating his day pass from a court-mandated treatment center.
A judge approved his release from jail on condition that he is enrolled in rehab. Once transferred to the rehabilitation facility, O'Neal will spend up to 12 months there.
The length of his stay will depend "on the treatment team's decision," his lawyer, Richard Pintal, told E! News.
O'Neal is expected back in court March 3 so a judge can check on his progress.