Joseph immigrated to the United States in 1933 after finishing university in Leipzig. His parents and brother had left Germany earlier for the United States. Joseph attended Columbia University. From 1940 to 1943 he was assistant editor for a New York German-Jewish newspaper. In 1944, he worked in the American embassy in Britain as a propaganda analyst. He went to Nuremberg, Germany, as an interpreter in 1946. He analyzed materials and transcripts, and participated in many interrogations for the Nuremberg trials.
There was no emotion. It was what he called a hard duty. He took no pleasure from it. He derived no pleasure. I said, "Didn't you have fun doing that?" I wanted to test him and see whether he was a sadist. He was no sadist. He was perfectly normal. He was doing his duty. I really believe he was doing his duty. He was doing his...believed he was doing his duty. He considered that his duty, and he shut his eyes to the abnormality of this kind of thing he was doing to the, to the abyss, the incredible abyss to which human beings can descend in order to perform duties of that sort. To which performance I think a normal person would revolt. Rather die himself than do it himself. I always figured I'd rather commit suicide. I'd die fighting against the Nazis than do anything at their behest.