Okla. Stat. tit. 62 § 443
The procedure for the making of an appropriation for the aforesaid purpose from such sinking fund and for the levy of a tax of not to exceed one (1) mill annually, shall be by resolution in which a majority of the board of county commissioners shall concur; and provided further, that the funds herein provided for shall not be used for the purpose of purchasing a site for the construction of the buildings herein provided for; and providing further, that in the event time warrants are issued for the aforesaid purposes, the county treasurer of any such county is hereby authorized to invest any available sinking fund money of such county in any such time warrants; and any such investment so made is hereby ratified and approved.
Okla. Stat. tit. 62, § 443