Dwain Johnson pleaded guilty to aggravated battery/discharge of a firearm, will provide sworn statements against his co-defendants and will cooperate with future investigations, according to court records.
The count on which Johnson pleaded guilty carries a minimum mandatory term of six years in prison and a maximum of 30 years.
SEE MORE: 4th suspect charged in murder of retired Chicago firefighter during Morgan Park attempted carjacking
CPD release surveillance video of Morgan Park shooting that killed retired Chicago firefighter
Closing arguments were ongoing Wednesday morning for Jaylen Saulsberry and Devin Barron, who were also charged in Chicago Fire Lt. Dwain Williams' murder.
Prosecutors have said Barron and Saulsberry tried to carjack Williams outside of a popcorn shop in the Morgan Park neighborhood in 2020.
He took out his own gun to defend himself when he was shot and killed.
Williams, 65, spent 28 years with the Chicago Fire Department and later worked at the Chicago Office of Emergency Management and Communications, specializing in coordinating the city's surveillance cameras.
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