We are expecting to learn more about the moments before and after Officer Martinez, who police allege was shot and killed by Darion McMillian earlier this week.
The 23-year-old Harvey man faces two counts of first degree murder attempted first degree murder unlawful use of a weapon and more.
Chicago police said Officer Martinez and his partner approached a car that was blocking traffic Monday night near 80th and Ingleside when McMillian in the passenger seat reached for a bag on the floor, ignoring police commands and pulled out a fully automatic handgun.
CPD said McMillian shot and killed Officer Martinez along with the car's driver in a barrage of gunfire.
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Police said he pushed the driver out of the car so he could climb behind the wheel and speed off.
Police alleges McMillian dragged Martinez's partner, who fired a single shot into the ground.
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CPD said McMillian then crashed into a woman's first floor apartment on the next block used a knife he found to cut off an electronic monitoring bracelet before trying to run away and being arrested by police.
Mayor Brandon Johnson spoke Wednesday during a police news conference.
"Officer Martinez saved lives even though he knew it could cost him his own," Johnson said.
Will County court documents show McMillian tried to "...defeat a drug screening test..." two months ago, a non-detainable offense under the SAFE-T Act.
That's why a judge ordered McMillian to wear an electronic monitoring bracelet he allegedly cut off.
Documents also show McMillian was released from prison last July after serving a more than three years on a separate aggravated discharge of a firearm charge.
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