He then received a Juris Doctor from Northwestern University Pritzker School of Law, cum laude, in 1987,[2] and was inducted into the Order of the Coif.

[7] In 1995, Cummings, alongside Barack Obama, represented ACORN, a voter registration organization that advocates for low- and moderate-income families in suing the State of Illinois in seeking to have it comply with the National Voter Registration Act of 1993.

[8][9] In 2009, Cummings secured a $630,000 settlement for a class of black workers with Area Erectors, Inc., who alleged termination based on race.

[12][13] In 2021, Cummings ordered the pretrial release of Jim Bob Elliott, a member of the group the Proud Boys, who was arrested for his participation of the January 6 United States Capitol attack.

[14][15] In December 2021, Cummings was recommended to the president by Illinois Senators Dick Durbin and Tammy Duckworth.