Penal Code § 1373
CHAPTER 6. Inquiry into the Competence of the Defendant Before Trial or After Conviction
The expense of sending the defendant to the state hospital or other facility, and of bringing him or her back, are chargeable to the county in which the indictment was found, information was filed, or revocation proceeding was held; but the county may recover the expense from the estate of the defendant, if he or she has any, or from a relative, bound to provide for and maintain him or her.