Convicted felon Shomari Legghette is charged with first-degree murder.
"The evidence will prove to you that when the defendant executed Cmdr. Bauer, he did so for no reason other than his own desperate attempts to avoid the police," Assistant State's Attorney Risa Lanier said Tuesday.
WATCH: PROSECUTOR GIVES OPENING STATEMENT IN CPD MURDER TRIAL
Legghette's attorney, Scott Kamin, said his client was downtown taking a perspective girlfriend to lunch at the time of the shooting. While Kamin admits the four-time felon was a drug dealer, he said Legghette fired shots in self-defense after Bauer put him in a headlock. He said Lagghette was unaware Bauer was a police officer.
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"It's a tragedy, but Cmdr. Bauer brought it on himself," Kamin said.
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Judge Erica Reddick denied a last-minute motion to move the trial out of town because of pre-trial publicity, including an ABC 7 Chicago I-Team report, which featured a letter to the I-Team, in which Legghette made the same claim that Bauer never announced that he was a police officer.
Prosecutors questioned the first witness about whether Bauer was wearing his uniform. Police Cmdr. Warren Richards, who was at a meeting with Bauer earlier, said he was. Prosecutor said Bauer's gun was still in his holster when he was shot. And the seven bullets that hit him trace to the 9 mm Glock handgun Legghette was carrying.
"He knew that Paul Bauer was a police officer ... and he killed him for it," Lanier said.
The state also called numerous witnesses Tuesday who identified Legghette as the man seen wrestling with Bauer before tumbling down the stairwell near the Thompson Center two years ago. Witness William Dvorak said he then heard a series of gunshots coming from the bottom of the stairwell.
The trial is expected to last a week and a half. In his letter to the I-Team, Legghette said he plans to testify in his own defense.
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Bauer was killed on Feb. 13, 2018 after police said he confronted Legghette at the Thompson Center. Police said after Bauer chased him into a stairwell, Legghette opened fire during a struggle.
Bauer was in full uniform the day he was killed, authorities have said. He had just finished a meeting at City Hall when he heard a radio call for a fleeing suspect. He spotted Legghette who appeared to be the suspect and chased him into a stairwell.
Legghette, who was wearing body armor that day, is the only live witness to the stairway struggle outside the Thompson Center and Bauer's final moments. Bauer was shot seven times.
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