 During his internment in Theresienstadt, Spier also cooperated with the Germans by assisting with the film "Theresienstadt, ein Dokumentarfilm aus dem jüdischen Siedlungsgebied".Jo Spier moved to the United States in 1951 with his family and continued to work until the end of his life.Spier died in Santa Fe, New Mexico on 21 May 1978.