Cal. Pub. Cont. Code § 10103.5

Work performed by prisoners pursuant to an order by the Secretary of the Department of Corrections and Rehabilitation or by the California Correctional Training and Rehabilitation Authority is not subject to this chapter, provided that the total cost of a project for the construction of new, previously unoccupied prison facilities or additions to an existing facility shall not exceed fifty thousand dollars ($50,000) unless it is first approved by the State Public Works Board.