"In the 2015 Massachusetts case, the court refused to allow the introduction of ShotSpotter audio after the defendant argued the audio was captured and obtained in violation of that state’s wiretap laws. Police in that case requested and received an extended audio clip from the company that captured people discussing the shooting, including one calling out the defendant’s name."

In theory any evidence from those audio recordings is tainted and no longer admissible, therefore police should want to avoid listing to any of it. But... by not bringing it up in court police can use parallel construction to get around those issues.