By Chris Tye

CHICAGO (CBS) — Mayor Lori Lightfoot’s promises to reduce gun violence swept her into office with an overwhelming 2019 win. After a violent weekend with 73 people shot, 10 of whom were killed, Lightfoot has declined to ask for help from the Illinois National Guard. But she has eagerly accepted help from the Department of Justice. They are decisions that help shape a playbook to thwart what the mayor herself calls a crisis of violence in Chicago.

CBS 2 dug into city crime data in the three years prior to Lightfoot taking office. In 2016, 4,321 people were shot in Chicago. Three years later that number dropped to 2,664. With 1,657 fewer victims, that was a 38% drop.

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But as 2019 gave way to 2020, the first full year for the new mayor, the trend line was about to reverse sharply. In Chicago in 2020, 4,135 people were shot — nearly 1,500 more victims than the year prior and a jump of 36%.

Through July of 2021, Chicago has seen 2,528 people shot. That is 10% more than the same stretch last year.

Given the violence of this weekend, CBS 2 wanted to ask Lightfoot why she thinks the trend is reversing, but she canceled her only public appearance Monday.

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In an interview she gave last month to The New York Times podcast “SWAY,” Lightfoot frames these trend reversals as a result of the pandemic.

“Prosecutor, courts, jails reatreated. Our COok Court system for crime trials still hasn’t fully reopened,” she said.

And Chicago is not alone. In the first half of 2021 New York has seen a 99% jump in shootings compared to pre-pandemic 2019. Nationally, the Council on Criminal Justice says the nation has seen a 42% jump in homicides in the first hall of 2021 as compared to 2019.

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The game of catchup continues in the Cook County Court system. To try to play catchup the chief judge has added space for more proceedings and bringing in backup judges from the suburbs and former criminal court judges.