Alameda County Superior Court Judge Evelio Grillo issued the order Tuesday but gave Jahi's family until 5 p.m. Dec. 30 to file an appeal. She will stay on life support until then.
Dr. Paul Graham Fisher testified during a hearing that Jahi meets all the criteria of brain death. Fisher's evaluation was the second to reach that conclusion.
Jahi was declared brain dead on Dec. 12 at Children's Hospital in Oakland. Doctors want to remove Jahi from life support, but her family is fighting to keep the teen connected to a breathing machine.
The Associated Press contributed to this report.