If the amount of compensation awarded to the defendant by final judgment in proceedings pursuant to this chapter is twenty percent greater than the plaintiff's final offer which shall be filed with the court having jurisdiction over the action at the time trial is commenced, and if that total award exceeds seven hundred dollars, the court shall, in addition to such taxable costs as are allowed by law, allow reasonable attorney fees and compensation for not more than two expert witnesses, all as determined by the court.
SDCL 21-35-23