But Judge Timothy Ryan ordered deputies to "use any means necessary" to get the 23-year-old mother to Wednesday's hearing.
Johnson is being held in Maricopa County jail in connection with her son's disappearance.
Gabriel was 8 months old when he was last seen in late December in San Antonio, and police don't know whether he's dead or alive.
Police say Johnson drove the boy to San Antonio from Tempe, stayed about a week, and then took a bus to Florida without him.
She was arrested Dec. 30 in Florida and is charged in Arizona with kidnapping, child abuse and custodial interference.MEDIA
PICTURES: Baby Gabriel Johnson Missing
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