During that period, he tried twelve jury and two bench trials to successful resolution on behalf of the government, and argued multiple cases on appeal before the Seventh Circuit.

[1] Before becoming a judge, he was a partner in the Indianapolis office of Faegre Baker Daniels LLP, where he served as co-chair of the firm's white collar criminal defense and investigations practice.

[1][2] Hanlon has served as an adjunct professor at the Indiana University Robert H. McKinney School of Law, where he taught courses on white collar crime.

He was nominated to the seat that was vacated by Judge William T. Lawrence, who assumed senior status on July 1, 2018.

[10] On June 16, 2023, he issued an order stopping an Indiana ban on puberty blockers and hormones for transgender minors from taking effect as scheduled July 1.