[2] Cohn was born and raised in New York; married Dora (née Marcus; 1892–1967) in 1924, when he was the First Assistant District Attorney for Bronx County.
[3][4] Their only son, renowned attorney Roy Cohn, was born in 1927.
[7] A 1931 decision by Cohn stripped control of amateur boxing in New York from the Amateur Athletic Union (AAU) and placed it under control of the New York State Athletic Commission.
[8] In April 1937, Governor Herbert H. Lehman promoted Cohn to a five-year term on the New York Supreme Court, Appellate Division, where his fellow Justices included Irwin Untermyer.
[9] He spearheaded a program for accreditation by the American Bar Association for his alma mater, New York Law School, starting in 1947, which was successful, in 1954.