Mallet That Killed Nurse - Ypsilanti Police Capt. Emil Susterka holds the heavy rubber mallet used in the brutal Sunday morning slaying of St. Joseph's Mercy Hospital Nurse Pauline Campbell. Police found the weapon in an Ypsilanti garage where Jacob M. Pell, 18, was employed. William R. Morey, also 18, admitted to police early this morning that he had struck the 34-year-old Miss Campbell twice with the mallet, causing her death. Pell and Morey, both of Ypsilanti, and David L. Royal, 17, of Milan, broke down under police questioning early this morning, ending a four-day investigation.