Any litigation tax pursuant to any private act of the general assembly shall be suspended during such time and from time to time, on the basis of actuarial standards certified by the actuary retained by the board, as any retirement plan for judges funded in part by such litigation tax is determined by the state treasurer to be actuarially overfunded; thereafter, such litigation tax may be resumed upon determination by the state treasurer that the plan is not overfunded. During any period of time that such local tax is not suspended, the general sessions tax provided in § 17-512 applicable to cases taxed pursuant to any such private act shall be reduced to thirty cents (30¢).