Pinder joined the Army from Burgettstown, Pennsylvania, and by June 6, 1944 was serving as a technician fifth grade in the 16th Infantry Regiment, 1st Infantry Division. On that day, he participated in the Allied landings near Colleville-sur-Mer, France. Despite being twice wounded, Pinder refused medical attention and continued to gather communications equipment in order to establish a radio link on the beach before receiving a third and fatal wound. He was posthumously awarded the Medal of Honor seven months later, on January 4, 1945.