The Democratic candidate overwhelmingly won the 2016 race against her opponent, Republican Christopher Pfannkuche, on the promise of "fixing a system that we know needs repair."
Foxx's predecessor, Anita Alvarez lost her bid for reelection following widespread criticism over how she handled the 2014 Laquan McDonald police shooting.
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Foxx also came under scrutiny in the past year following her decision to drop charges against "Empire" actor Jussie Smollett. Smollett has been accused of faking a hate crime and was indicted by a grand jury on 16 counts of disorderly conduct for filing a false police report in late January.
Text messages obtained by the ABC7 I-Team show Cook County State's Attorney Kim Foxx thought the number of charges filed against Smollett were excessive.
The Chicago police union and dozens of Cook County police chiefs banded together in the middle of the controversy to announce a "no confidence" vote in Kim Foxx as the State's Attorney for her involvement in the Smollett case.
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Foxx's chief spokesperson and two top executives coincidentally left the Cook County State's Attorney's Office in April without reason for their departure.
Then in June, a Cook County judge ruled to appoint a special prosecutor to review State's Attorney Kim Foxx's handling of the Smollett case. In his ruling, the judge questioned Foxx's decision to appoint a deputy to oversee the Smollett case, saying that she did not have the authority to do so.
Two months later Foxx secured Cook County Democrats' endorsement for the 2020 primary, despite the firestorm.
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"When I ran in 2015, I said I was running to transform the way the Cook County State's Attorney's Office operates," Foxx said in April.
In her ad released this week, she said, "I'm running again because we're only getting started."