02/07/2008 at 01:00 AM EST
was released early
from UCLA Medical Center's psych ward because a court representative found "no just cause" for the hold, a source tells PEOPLE.
The doctor overseeing Spears's care had wanted her to stay, (as did her parents
), but the decision was overridden by the court representative, the source said.
The source said that the doctor who was vetoed was not Spears's psychiatrist Dr. Deborah Nadel, but another attending doctor at UCLA. Once Nadel issued the singer's 72-hour hold at UCLA, Nadel was not involved in Spears's hospitalization, the source said.
The decision followed regular procedure for any patient on a 14-day hold.
The procedure calls for a hearing at the hospital to find out whether the hold is justified. The rep for the court, called a "hearing referee" – who is usually a lawyer – interviews the patient and doctor to determine if there's "just cause" for detainment.
"This is when law and medicine collide," says attorney Terry K. Wasserman, who's not involved in the Spears matter, "when a lawyer can override a doctor's opinion."