Kern County Judge Bernard Barmann issued a temporary restraining order to prevent enforcement of the mandate as the court considers a preliminary injunction request.
The vaccine mandate was scheduled to take effect Friday. It will continue to apply to other employees who work in state prisons with health care facilities.
The California Correctional Peace Officers Association (CCPOA) has opposed vaccine mandates across the state. The union represents about 28,000 officers statewide.
"Mandating universal vaccination of staff, on the other hand, at this point in time, seems at odds with the dramatic reduction in COVID-19 infection rates within the prisons, and throughout the State generally, in recent months," The CCPOA said in its preliminary submission (pdf).
"The Court should resist Plaintiffs' request that staff be subjected to a mandatory vaccination order," the submission added.
The state plans to appeal the ruling.
"On August 19, 2021, the California Department of Public Health (CDPH) issued an order for paid and unpaid individuals who are regularly assigned to provide health care or health care services to incarcerated people, prisoners, or detainees to show evidence of full vaccination against COVID-19 by October 14, 2021, unless they qualify for an accommodation based on a sincerely held religious beliefs or due to qualifying medical reason(s)," according to the California Department of Corrections and Rehabilitation (CDCR).