(a) In all judicial districts in this state in which there is a county with more than one hundred twenty thousand (120,000) inhabitants according to the most recent federal census and where there are more than two (2) divisions of the circuit court and more than one (1) municipal court with countywide jurisdiction, and in which county the office of the prosecuting attorney is maintained permanently in the county courthouse, the prosecuting attorney may expend from the contingent fund provided by the county such sums as are necessary for the purchase and maintenance of an adequate law library.
(b) The law library, when purchased, shall become the property of the county.