In 1936 he concluded his education of physics at McGill University in Montreal and obtained his doctorate in 1940.
David Shugar was detained by the Royal Canadian Mounted Police in 1946 and charged with conspiring to hand over official secrets to the Russians.
He continued working as a researcher, first at the Pasteur Institute in Paris in the years 1948–1950, and later at the Center of Nuclear Physics of the Free University of Brussels until 1952.
Co-author of the first book on Photochemistry of Nucleic Acids (Shugar, McLaren, Pergamon 1964).
His spouse, Professor Grace Wales Shugar (1918 - 2013), created the Center of the Developmental Psycholinguistics at the Faculty of Psychology of the University of Warsaw.