Now its come to light that a great many (unseen) UFO files and research documents were kept and preserved by his family at his home in Tucson,Arizona for over twenty five years:
From the MUFON Journal, January 1997, Number 345DR. JAMES E. McDONALD'S UFO FILES
by Ann Druffel
The voluminous UFO research files of a fearless scientist. Dr. James E. McDonald, have lain in a special "UFO room" at his home in Tucson, Arizona for twenty-five years, lovingly protected by members of his family. McDonald was a high-profile contributor to scientific UFO research, beginning in the Spring of 1966 and continuing until his tragic death in June 1971.