He is a professor at Columbia University Law School in New York City and at the École des hautes études en sciences sociales (EHESS) in Paris.

His most notable clients include Walter McMillian,[4] and Doyle Lee Hamm,[5] whose 2018 execution was called off because an IV line could not be set.

In 2012, he published, The Illusion of Free Markets: Punishment and the Myth of Natural Order which explored the relationship between laissez faire and mass incarceration.

He is the editor of the French edition of Foucault's 1972 Collège de France lectures on Théories et institutions pénales (published by Gallimard in 2015)[12] and Foucault's 1973 Collège de France lectures on La société punitive (published by Gallimard in 2013).

[13] He is the co-editor, with Fabienne Brion, of Foucault's 1981 Louvain lectures Mal faire, dire vrai.

"[19] In 2015, Harcourt was awarded an honorary doctorate from the Aix-Marseille University in France for his contributions to contemporary critical thought.

[20] He is also the recipient of the 2009 Gordon J. Laing Prize for his 2007 book, Against Prediction: Profiling, Policing and Punishing in the Actuarial Age.

[21] In 2019, Harcourt received from the New York City Bar Association the Norman J. Redlich Capital Defense Distinguished Service Award for his longtime advocacy on behalf of individuals on death row.