1 The dispositive issue presented is whether a 1979 amendment of the Political Subdivision Tort Claims Act (Act) should be given retrospective effect thereby barring the claimants action for wrongful death. The trial court held that the amendment operated retroactively, that the notice of claim requirement and the time-bar limitation of 51 O.S. 1981 ? 156 were applicable, and entered summary judgment against the claimant. We find that because a substantive right was involved, the trial court erred in retroactive application of the statute.