[3] From 1924 to 1927 he taught Equity, Trusts, and Quasi-Contracts at the Notre Dame Law School.
[6] He was an instructor in legal history, mortgages, and bankruptcy law as well as a member of the school's athletic council.
[1] Hadley served as the president of New England Anti-Gambling Association, an organization created to oppose the legalization of parimutuel betting and other forms of gambling in Massachusetts, and the Anti-Vivisection Society of America, which opposed the use of animals in medical research.
[8][9] In 1941, Hadley served as a constitutional advisor on emergency war legislation for the Commonwealth of Massachusetts.
During World War II, Hadley served in the United States Army, where he rose from the rank of private to major.