The Pennsylvania Supreme Court last week ruled that evidence derived from Pittsburgh’s ShotSpotter gunshot detection system was properly allowed in the prosecution of a now-72-year-old North Side man, but two justices expressed concern about the admissibility of tech-derived reports.

The six sitting justices ruled unanimously that Allegheny County Court of Common Pleas Judge Jill Rangos did not err when she allowed prosecutors to submit, and a City of Pittsburgh police officer testify regarding, a ShotSpotter-generated report in a case against Angelo Weeden. 

He was charged in a 2018 incident involving shots fired at a car in which a former romantic partner and others were riding. Court records indicate two bullet holes in the car door, but no injuries. A jury convicted him of aggravated assault and related charges, and Rangos sentenced him to 10 to 20 years of incarceration.



Weeden’s attorney, Justin Romano, appealed the conviction, arguing that ShotSpotter’s “inherent unreliability” and the failure of the prosecution to present any witness who could be effectively cross-examined about its methodology, resulted in a violation of Weeden’s right to confront an accuser.

ShotSpotter installs acoustic sensors in locations like the tops of buildings, streetlight poles and cellphone towers. The sensors listen for loud sounds, and an algorithm calculates the location. The technology, plus human reviewers, determine whether the sounds are likely gunfire. The information is then transmitted to the county 911 system, which determines whether to dispatch police.

A light pole on Mohler Street in Homewood North. Light poles are among the pieces of infrastructure that can include ShotSpotter acoustic sensors in around one-third of the City of Pittsburgh. (Photo by Stephanie Strasburg/Public Source)
A light pole on Mohler Street in Homewood North. Light poles are among the pieces of infrastructure that can include ShotSpotter acoustic sensors in around one-third of the City of Pittsburgh. (Photo by Stephanie Strasburg/Public Source)

The state Supreme Court ruled that the ShotSpotter-generated report tied to Weeden’s charges did not constitute testimony, because it was just a repackaging of data generated by ShotSpotter at the time the shots were fired. Based on U.S. Supreme Court precedent allowing admission of evidence gathered in an “ongoing emergency,” the state’s high court found that use of the report did not run afoul of Weeden’s rights as a defendant under the Sixth Amendment.

Justice David Wecht, while concurring with the opinion because of federal precedents, wrote that admitting such reports “without a corroborating witness on the stand to undergo cross-examination hardly contributes” to the goal of fair trials. “To the contrary, it all but guarantees the opposite.” Unless the U.S. Supreme Court “reverses course,” he wrote, “this inequity shall continue.”

Justice Kevin Brobson, in another concurring opinion, wrote that “as technology advances, particularly in the field of artificial intelligence, these concerns will continue to arise.” He recommended that the state court system’s Committee on Rules of Evidence examine concerns with the use of emerging technology as evidence.

Pittsburgh began using ShotSpotter in early 2015 over a 3-square-mile area in the northeast of the city, with officials billing it as a way of summoning police and medical assistance to gunshot victims even when no one calls 911. It has since been expanded to cover roughly one-third of the city.

The city pays ShotSpotter around $1.2 million a year and the current contract runs through 2025.

Rich Lord is the managing editor at PublicSource and can be reached at rich@publicsource.org.

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Rich is the managing editor of Pittsburgh's Public Source. He joined the team in 2020, serving as a reporter focused on housing and economic development and an assistant editor. He reported for the Pittsburgh...