Sierra Evans,19, was gunned down on Saturday in the 9500-block of S. Avenue N in the city's East Side neighborhood.
17th Ward Alderman David Moore said officers responded when a neighbor called 911 at 9 a.m. However, that was hours after the shooting actually happened.
"What saddens me is that a young lady had to, number one, die alone, but two, possibly could have gotten some help, some immediate help, and possibly could have survived," Moore said. "And possibly could have had ...enough evidence or captured the person that had done this so that we can bring justice."
ShotSpotter was deactivated on September 23, days before Evan's death.
The city said it's looking for an alternative to the gunshot detection technology.
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