[11] Fleming received a Bachelor of Arts in political science from the University of Missouri in 1977.

[14] He then attended Princeton University, earning a master's degree and, in 1988, completed a Ph.D. in politics with the dissertation,[7] "Constitutional Constructivism,"[15] under the supervision of Walter F. Murphy[16] and Sanford Levinson.

[15] Before becoming a law professor, Fleming was an attorney in the litigation department at Cravath, Swaine & Moore in New York City from 1986 to 1991.

[20] At Fordham and Boston University, Fleming has organized, co-organized and published numerous conference volumes in constitutional theory and legal philosophy,[21][22][23][24][25] including volumes on the work of John Rawls[26] and Ronald Dworkin.

[27] Fleming was the Editor of Nomos, the annual book of the American Society for Political and Legal Philosophy.