When a man died after taking fentanyl pills bought in Northern Kentucky, investigators turned to his cellphone to trace the source of the deadly drugs.
Posing as the dead man, authorities used messages stored on his cellphone to order more fentanyl pills, launching a series of undercover meetings that led them up the supply chain and exposed what prosecutors described as a wide-reaching, Cincinnati-area trafficking network.
More than two years later, that cellphone trail culminated in a 25-year federal prison sentence for Juan McKenzie Jr., whom prosecutors identified as a high-level supplier of the drugs that flowed through multiple dealers before reaching the man who died.
U.S. District Judge David Bunning imposed the sentence on Sept. 11 after
25-year-old McKenzie pleaded guilty in May to aiding and abetting the distribution of fentanyl resulting in death.
Prosecutors said that McKenzie is a “zealous drug trafficker” whose near-daily sales of fentanyl pills to lower-level dealers created a chain of transactions that ended with a fatal overdose in early 2024.
The federal case in Covington was built largely on evidence gathered through undercover stings and text messages that allowed investigators to work their way from street-level sellers to the supplier they say helped flood the streets with fentanyl.
In a presentence court filing, Assistant U.S. Attorney Andrew Spievack said McKenzie “tapped an immense supply of drugs to, in turn, enable drug dealers to fan out into communities spreading lethal drugs.”
“The duration, quantity, and frequency of [McKenzie's] fentanyl trafficking was so significant that death was inevitable,” Spievack said. “The only question – now answered – was when one would catch up to him and put a stop to his crimes.”
Lee Metzger, the attorney representing McKenzie, said that his client faced a minimum of 30 years with a maximum of life in prison under federal sentencing guidelines.
“Although we had hoped for a lower sentence,” Metzger said in a statement, “I am grateful to the court for thoughtfully considering our arguments and for giving Mr. McKenzie an opportunity at redemption – even if it is a quarter-century down the line.”
Feds climbed the supply chain through undercover drug deals
Andrew Rossi bought pills from McKenzie and sold about 30 of them to another dealer, Steffany Keene, in February 2024, prosecutors said. During a drug deal in Boone County, Keene sold four pills to a man identified in court filings only by his initials.
The man took the pills and “never woke up,” prosecutors said.
Investigators used messages on the man's cellphone to arrange another purchase from Keene, who did not know her customer had died. Drug enforcement agents arrested her at the meeting and seized both drugs and her phone.
Using Keene's phone, agents then arranged to meet with Rossi while posing as her. When they arrested Rossi later that day, he told investigators he had just picked up 55 pills from his supplier, noting he had been buying similar quantities nearly every day for weeks. Rossi also said the supplier regularly received shipments of 10,000 fentanyl pills through the mail.
Prosecutors said messages on Rossi's phone identified McKenzie as the supplier. They added that Rossi either used the drugs himself or redistributed them to customers and other dealers.
Rossi and Keene later pleaded guilty. Court records show Rossi was sentenced to 12½ years and Keene was ordered to a 12-year prison term.
Prosecutors: McKenzie ‘glorified’ drug trafficking
Prosecutors described McKenzie as a full-time drug trafficker, working his phones all day, every day to organize sales, even on holidays.
Despite a 2020 fentanyl-trafficking conviction, they said, McKenzie continued selling large quantities of narcotics and “glorified his chosen criminal profession.”
Text messages showed him trafficking not only fentanyl but also cocaine, marijuana and Xanax, prosecutors said. They alleged he had been dealing drugs since at least age 18.
Court filings describe McKenzie's "semi-sophisticated" efforts to avoid law enforcement finding out about his drug enterprise. He regularly switched phones, used "no-contact" drops and changed meeting locations. Prosecutors said McKenzie also advised others to delete messages and conceal license plates, though he sometimes conducted business at his family's home.
A federal grand jury indicted McKenzie in June 2025 in connection with the overdose death. When officers arrested him on unrelated charges in Ohio two months later, they collected his four cellphones.
Before U.S. Drug Enforcement Administration agents could obtain a seizure warrant, someone picked up the phones from the jail on McKenzie's behalf. Agents contacted that person and requested the devices.
According to prosecutors, the person agreed but first alerted McKenzie, who instructed them to destroy the phones or wipe their contents because it would be "very bad" if investigators saw what was on them.
Agents ultimately obtained the phones, secured search warrants and recovered evidence they said corroborated McKenzie's trafficking operation. The devices contained photos of packages shipped from California to Cincinnati addresses and shipment-tracking screenshots. Prosecutors said there were also messages with another dealer who bought drugs and guns from McKenzie.
Case was ‘sobering’ for McKenzie, attorney says
Metzger, the defense attorney, wrote in a court filing that McKenzie had a difficult childhood, including time in the foster care system.
He also cited the unexpected death of McKenzie’s mother during his teenage years and the fatal shooting of his older brother shortly after in 2018.
“His life to this point has been difficult,” Metzger said.
While McKenzie has prior convictions, Metzger noted that none resulted in lengthy jail or prison sentences.
“Thus, this offense marks the first time he has ever faced a significant period of incarceration,” Metzger said. “It has been sobering.”
This article originally appeared on Cincinnati Enquirer: Feds used a dead man's phone to trace a chain to a 'zealous drug trafficker'
