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Pittsburgh Prosecutors Relied On Man Who Allegedly Killed Baby As Witness In Bungled Case

Documents obtained by The Appeal raise questions about a Pittsburgh-area mass shooting case that fell apart due to prosecutorial misconduct.

Allegheny County DA Stephen A. Zappala, Jr.
Photo illustration by Elizabeth Brown. Photo of District Attorney Stephen Zappala Jr. from AP Photo/Keith Srakocic.

Pittsburgh Prosecutors Relied On Man Who Allegedly Killed Baby As Witness In Bungled Case

Documents obtained by The Appeal raise questions about a Pittsburgh-area mass shooting case that fell apart due to prosecutorial misconduct.


In 2017, Gregory Parker admitted to Pittsburgh-area law-enforcement agents that he was involved in the 2013 murder of Marcus White, Jr., a 15-month-old baby. But Parker, now age 22, was not arrested—he was the Allegheny County district attorney’s star witness in a 2016 mass shooting in Wilkinsburg, a suburb about nine miles from Pittsburgh. Five people were killed in the incident, including a pregnant woman. Prosecutors relied on Parker’s testimony as a jailhouse informant in their case against two men—Cheron Shelton and Robert Thomas—accused of murder in the mass shooting. Prosecutors had been seeking to put both men to death.

But the prosecutors’ gamble backfired spectacularly: neither Shelton nor Thomas were convicted. In February, Shelton was acquitted in after his attorneys said prosecutors waited until the night before the trial to divulge evidence that they’d struck a deal with Parker in exchange for his testimony, in violation of the U.S. Supreme Court decision Brady v. Maryland. So, the 2016 mass shooting remains unsolved. And, after prosecutors finally charged Parker with killing White this year, his family filed a federal lawsuit against the Allegheny County DA’s office alleging it knew of Parker’s culpability in the murder for years and chose not to arrest him.

Now, The Appeal has obtained even more evidence that defense attorneys say DA Stephen Zappala’s office hid from them—including a document alleging that law enforcement agents recorded an interview with Parker in 2018 that was not entered into evidence during Shelton’s trial until Shelton’s defense team complained.

“In 2018, the Allegheny County DA’s office made the decision to release Gregory Parker, a confessed baby killer, in order to salvage their death penalty case against Cheron Shelton and Robert Thomas,” Paul Jubas, an attorney representing both Shelton and White’s family, told The Appeal. As part of the family’s complaint, they’ve demanded that Zappala’s office be taken off the Parker case.

“They decided to use Gregory Parker in the Wilkinsburg massacre trial, to release him after he confessed to killing baby Marcus, and to not charge him for killing baby Marcus, despite the fact that they knew that he gave false information about the Wilkinsburg massacre,” Jubas added. During the case, testimony from two other key jailhouse informants—Kendall Mikel and Frederick Collins—also fell apart under basic scrutiny, and prosecutors ultimately declined to call either Mikel or Collins to testify during the trial.

Representatives for the Allegheny County DA’s office did not respond to a request for comment from The Appeal. But in June, a spokesperson for the DA’s office told the media that the White family’s complaints were “wrong on the facts,” “wrong on the law,” and “frivolous.”


This series of bungled cases highlights law enforcement’s long-troubled use of jailhouse informants who agree to testify in separate legal cases in exchange for benefits such as reduced sentences.

Criminal legal reform advocates and law professors have long warned that jailhouse informants are incentivized to fabricate evidence. Jailhouse informants, wrote Harvard Law professor Alexandra Natapoff in a 2018 explainer for The Appeal, “are a particularly risky and unreliable category of criminal informant.” In 2015, the National Registry of Exonerations, a project of the University of Michigan Law School, found that 23 percent of all death penalty exonerations involved false jailhouse informant statements.  Furthermore, ProPublica reported last year that more than 140 people convicted of murder between 1966 and 2019 were exonerated because of false jailhouse informant testimony. Jailhouse informant rings have been uncovered in cities including Los Angeles, Detroit, and Chicago.

The Wilkinsburg mass shooting isn’t even the first mass shooting case tainted by an informant scandal in the last decade. In 2011, a gunman in Orange County, California, shot eight people, including his ex-wife, to death in a local salon. While the shooter, Scott Dekraai, ultimately pleaded guilty, his public defender, Scott Sanders, revealed that Orange County law-enforcement officials  had been secretly running an unconstitutional jailhouse informant program for years. Sanders accused Orange County prosecutors of planting an informant inside a local jail near Dekraai in order to elicit testimony from him. Then-California Attorney General Kamala Harris and the U.S. Department of Justice then launched probes into police informant usage, though no one was ultimately disciplined.


In the Wilkinsburg mass shooting case, prosecutors relied on three jailhouse informants against Cheron Shelton, and all three fell apart in their own unique ways.

Without testimony from these jailhouse sources, the Allegheny County DA’s office appeared to have a weak case. At around 10:45 p.m. p.m. on March 9, 2016, two people allegedly surrounded a backyard cookout in Wilkinsburg and opened fire. One shooter used a .40-caliber handgun and another used an assault-style rifle. The shooter with the handgun fired a blast meant to scare the people in the yard—and whoever used the assault rifle then shot people as they all tried to run inside the home.

But the evidence linking Shelton to the murder was circumstantial at best. The sole witness tying Shelton to the crime was Wilkinsburg Police Detective Michael Adams, who said he saw Shelton acting “weird” a few blocks from the shooting. Adams tried to speak to Shelton, but Shelton simply stared and didn’t answer any of his questions. (During the trial, prosecutors also didn’t disclose evidence proving that Adams had actually run Shelton’s license plate that day until after the trial began.)

To bolster their case, prosecutors relied on the three jailhouse witnesses, including two who initially claimed to have overheard Shelton and Thomas confess to the mass killing. The first witness, Kendall Mikell, told the media earlier this year that he’d previously been barred from working as an informant and had been paid under the table by police and the DA’s office. In February, the Pittsburgh Post-Gazette reported that the DA’s office had paid Mikell $1,756 from its “witness relocation fund” in 2016. Defense attorneys later stated in court filings that payments from the DA’s office to Mikell were not disclosed and that he was “purposefully” placed in a cell next to Shelton’s.

Prosecutors decided not to rely on the second witness, Frederick Collins, because of his history of outbursts during court proceedings. In 2015, Collins began screaming during a hearing related to a domestic dispute and threatened to kill a woman involved in the incident. Collins was charged, and then, during a hearing related to those charges, he threatened to murder the judge overseeing his case.

That left the third witness, Parker. In February 2017, Parker was indicted. Parker then began cooperating with Allegheny County law enforcement—and on Nov. 30 of that year, he agreed to a sit-down, recorded interview with prosecutors. During that interview, Neal Carmen, an agent with the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), was recorded saying that the government was “going to uphold our end, and we are going to do the best we can. There are guarantees in there that have already been talked about and are hoping to more than what is guaranteed, depending on what is needed.”  Carmen also stated that he hoped to get Parker “back on the street” so he could become a productive member of society.

A Pittsburgh Police detective then yelled: “Hey Neal, it is still recording you know.”

(In a deposition that occurred during Shelton’s and Thomas’s case, Carmen stated that he’d only “guaranteed” that he would inform a judge that Parker had been cooperating with law enforcement, but admitted that Allegheny County Police had offered to help relocate Parker and one of his family members.)

In a Jan. 30 legal filing, Shelton and Thomas’s defense attorneys said that prosecutors failed to turn over any records showing that Parker had struck any type of cooperation deal with the government until the eve of the trial. 

“Exculpatory evidence was withheld in clear violation of Brady under the guise that it was protected grand jury material from other cases when, in fact, it was not grand jury material,” Shelton’s lawyers wrote.


But that’s not the only evidence that appears to have gone undisclosed. According to ATF and Allegheny County Police investigative documents obtained by The Appeal, law enforcement officials interviewed Parker again on Feb. 15, 2018. An Allegheny County Police report shows that Parker said he “had information regarding the Wilkinsburg homicide where 6 people were killed.” A county detective, Todd Dolfi, wrote that Parker said he spoke to a man inside the jail nicknamed “Millhouze,” who explained that someone at the cookout had killed a friend of theirs, and that the two shooters opened fire in revenge. The police report stated that Allegheny Police recorded Parker’s interview, but Shelton’s lawyers told The Appeal the DA’s office also withheld the audio until the last minute.

Eventually, Allegheny County prosecutors stopped relying on Parker’s testimony. In February, a local judge dropped the case against Thomas, granting a motion stating that prosecutors had insufficient evidence to bring it to trial. Allegheny County Common Pleas Judge Edward Borkowski added that relying on jailhouse informants was “treacherous waters; we know that from experience.”

Later that month, a jury acquitted Shelton of every count against him—including five counts of murder, homicide of an unborn child, three counts of aggravated assault, three counts of attempted murder, one count of conspiracy, and six counts of reckless endangerment.

But Shelton wasn’t free for long: On February 25, a federal grand jury in the Western District of Pennsylvania indicted Shelton on charges of felony possession of a firearm and ammunition by a convicted felon. Shelton has a prior felony drug conviction, and investigators say that during the mass shooting investigation, they found a .22-caliber rifle and ammunition in his mother’s home. Importantly, however, prosecutors do not believe that gun was used in the 2016 cookout massacre. 

Shelton is still being held in jail pretrial.