CHICAGO (CBS) — The veteran Chicago cop on trial for his December 2013 shooting of two teenagers made a “split second” decision in what he believed to be a neighborhood full of guns, drugs and crime, his defense attorney told a jury Tuesday.

Officer Marco Proano made that decision after arriving at 95th and LaSalle on Dec. 22, 2013, where two fellow officers had crossed paths with a stolen Toyota packed with teenagers. The driver had fled, a BB gun had fallen out of the car, and the vehicle had suddenly begun to reverse with one teen hanging out of a window, the Chicago Sun-Times is reporting.

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Daniel Herbert, Proano’s attorney, said the officer’s state of mind quickly boiled down to this: “He knows something bad is happening, and ‘I need to do something.’”

Now, Proano is on trial at the Dirksen Federal Courthouse for the choice he made that night. Assistant U.S. Attorney Georgia Alexakis bluntly — and repeatedly — described Proano’s decision to jurors during opening statements Tuesday afternoon.

“The defendant pulled his trigger 16 times,” Alexakis said. “He emptied his clip. He used up every bullet in his gun.”

A police dashcam captured the shooting on video. In it, Proano suddenly steps forward, holding his gun sideways. Seconds later, he steps backward as the car reverses into view. Proano lifts his gun again with both hands, upright, and a flash can be seen as he appears to open fire.

One teen was wounded in his left hip and right heel. The other suffered a shoulder wound.

A grand jury indicted Proano a little less than a year ago on charges he violated the civil rights of the teenagers. He has been suspended without pay from the Chicago Police Department, the Independent Police Review Authority recommended his firing, and the city settled with the wounded teens for $360,000.

Now his trial is getting extra attention because Herbert also represents Jason Van Dyke, the Chicago police officer charged in state court with the murder of 17-year-old Laquan McDonald. Herbert told jurors Tuesday that Proano’s case is about neither race nor police abuse.

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“Is there police abuse out there?” Herbert said. “Absolutely.”

The McDonald shooting prompted a wide-ranging investigation of the Chicago Police Department by the Justice Department, which criticized CPD’s training efforts.

On Tuesday, Herbert appeared to use that finding in Proano’s defense, noting that the same federal government putting Proano on trial has found training at CPD to be deficient.

“He did what he was trained to do,” Herbert said of Proano.

Alexakis said Proano was still trained on very basic policing principles, and she said he was taught not to shoot at a moving vehicle unless someone’s life was in danger. Though the car only began to reverse when one of the teens lunged forward from the back seat and pushed the gas pedal with his hand, she said no one was in the vehicle’s path.

She also said no other officer at the scene fired a single shot.

Proano’s trial is expected to conclude by Labor Day.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2016. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)