CHICAGO (CBS) – Another Chicago police district is now equipped with crime-fighting tools being credited with driving down the number of shootings in the city.

But as CBS 2’s Mai Martinez reports, the technology and extra man power comes with a hefty price tag.

“Our goal is no violence in the city,” said Chicago Police Superintendent Eddie Johnson.

And Johnson said this technology is helping officers reach that goal.

It includes Shotspotter, a program which used sensors to detect shots fired, then pinpoints locations within second and directs officers to the scene five to seven minutes faster than a 911 call.

The Gresham district is the fifth in the city to receive the technology.

“These investments that we’re making have made us smarter and faster, especially in the districts that present the greatest challenges with violence,” Johnson said.

And according to CPD, shootings are down in all of those districts compared to 2016 – 38 percent in the 7th District, 27 percent in the 11th District, eight percent in the 9th District, and 14 percent in the 15th District. But murders continue to rise, with 387 this year compared to 378 last year.

“If we can follow the trend with the shooting coming down, the murders should follow at some point,” Johnson said.

But the progress comes at a cost – about $1 million per district for the technology and millions of dollars in overtime for officers on the streets.

Roughly $30.9 million in just the first three months of 2017 was spent on overtime. That is up about $6.5 million from the same time last year. Johnson concedes second quarter overtime, which will include the Memorial Day and Fourth of July holidays, will likely be much higher.

“It is our duty to the taxpayers to make sure were using it effectively,” Johnson said. “For me I don’t know if you put a price on people’s safety.”

Superintendent Johnson said the city’s 2-year hiring plan should eventually help tap down overtime, as hundreds of new officers are transitioned out of the academy and onto the streets.

Mayor Emanuel shared his opinion on the expansion of the program, as WBBM’s Jim Gudas reports.

After seeing drops in violent crime in five districts on the West and South Sides where cameras, computers and other tech were employed, the city’s now expanding them to a sixth district.

And Mayor Emanuel repeatedly told reporters the goal here is to help officers, not take their place.

“It makes officers smarter, more effective of where they are going to go, what they need, when they need to be there – but it helps them do their job,” he said.

Emanuel said the tech has helped free officers from other tasks, so they can spend more time on the streets and be more effective in fighting crime.

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