[2] From 1994 until 1995, Chang served as a law clerk for Judge James L. Ryan of the United States Court of Appeals for the Sixth Circuit.

[2][3] From 1997 to 1999, Chang served as an associate at the Chicago headquarters office of the global law firm Sidley Austin.

[2][3] In 2009, Chang submitted an application to an Illinois screening committee for one of three federal district judgeship vacancies.

On April 21, 2010, President Barack Obama nominated Chang to a federal judgeship to fill the seat vacated by Judge Elaine E. Bucklo, who assumed senior status on October 31, 2009.

[4] On December 18, 2010, the United States Senate confirmed Chang by unanimous consent.