perpetuation

transitive verb | \ pər-ˈpe-chə-ˌwāt \ | per·pet·u·ate

1. : to preserve or make available (testimony) for later use at a trial by means of deposition especially when the evidence so gathered would be otherwise unavailable or lost

   Note: Courts will not allow the perpetuation of testimony at a pretrial proceeding if it appears to be an attempt to fish for useful material.