In 1942 he was called to duty in the United States Army Medical Corps as chief psychiatrist for the 30th General Hospital in the European Theatre.
Along with psychologist Gustave Gilbert he administered the Rorschach inkblot test to the 22 defendants in the Nazi leadership group prior to the first Nuremberg trials.
[2] Upon honorable discharge in 1946, Kelley was appointed Associate Professor of Psychiatry at the Bowman Gray School of Medicine in North Carolina.
[4] Kelley committed suicide in front of his wife, father and oldest son on New Year's Day 1958 during a family gathering to watch the Rose Bowl game on television.
According to Psychology Today, Kelley was an alcoholic and despondent by that time and had a "history of dark moods"; he had also expressed admiration "for Göring’s control over his own death".