UPDATE: Mary Phillips has now been released from custody and given a citation. Jessica Simpson did not return.
Jessica Simpson went to jail Friday morning in West Hollywood, California -- but, not to worry, she herself was not in any legal trouble.
Los Angeles County Sheriff's deputies tell RadarOnline.com that Simpson was there to try to bail out her friend, makeup artist Mary Phillips.
Simpson was ready to pay her $250 bail, until deputies told her "she (Phillips) was too drunk to go home and needed to stay at the Sheriff's jail until she sobers up." So Jessica left the scene.
Phillips -- who has worked for Jessica in the past -- was arrested at 1:30am (PST) for allegedly being drunk in public at the Sunset Tower Hotel in West Hollywood.