Former Cook County state’s attorney candidate Clayton Harris III on Thursday will take over as chief of staff to House Speaker Emanuel “Chris” Welch, the speaker’s office confirmed on Tuesday.

Harris, who narrowly lost to Eileen O’Neill Burke in the Democratic primary for state’s attorney this spring, replaces Tiffany Moy, who has been Welch’s chief of staff since 2021.

The speaker also announced that Isabel “Izzy” Dobbel, political director at the Chicago Federation of Labor, will join his office later in January as deputy chief of staff.

Welch in a statement said Harris and Dobbel will continue efforts to improve and modernize the speaker’s office.

“I look forward to all we can accomplish together in the 104th General Assembly and beyond,” Welch said.

As a candidate for state’s attorney, Harris said he favored a “balanced” approach to public safety. O’Neill Burke, who positioned herself as tougher on crime, was better funded in the primary to succeed Kim Foxx, the outgoing top prosecutor.

Harris has previously leaned into his experience in management and government and as a Black man living on the city’s South Side. In the state’s attorney race, he had the backing of the Cook County Democratic Party and the Chicago Teachers Union.

Harris became an assistant state’s attorney in 1999, and has previously said it was “taxing to just see Black men coming through the system constantly.”

He worked with Mayor Richard M. Daley’s office starting in 2003, and later as general counsel at the Chicago Department of Transportation.

Harris’ role with Welch won’t be his first time running an office: he previously served as chief of staff for the Illinois Department of Transportation and as a deputy chief of staff for Gov. Rod Blagojevich, a job he held at the time Blagojevich was arrested and charged with political corruption.

Blagojevich’s chief of staff was also arrested, and Harris then took over that job, though he has said he is not a political supporter of Blagojevich.

Harris has a law degree from Howard University.