A Bristol Township drug dealer was sentenced today to serve 12 ½ to 25 years in state prison for selling the drugs that caused a Levittown man to fatally overdose.

Derron Thompson, 26, pleaded guilty today in Bucks County Common Pleas Court to drug delivery resulting in death and an array of other drug and firearms offenses.

Thompson, who told police he sold drugs to support his family, admitted selling 29-year-old Tyler Mulhern the fentanyl that killed him on Jan. 10, 2017.

Mulhern was found unresponsive on a bathroom floor of his family’s home on Sugarmaple Drive when his father came home from work. Efforts by paramedics to revive him failed.

The victim’s father gave police permission to search his son’s phone, yielding text messages and calls that led them to Thompson.

At about 1 p.m. that day, investigators determined, Mulhern had bought several blue wax paper envelopes believed to contain heroin from Thompson outside the Levittown Trace Apartments on Ford Road, where Thompson resided.

Authorities believe he overdosed about an hour later. An autopsy determined that Mulhern died of a fentanyl overdose.

At the time, Thompson already was under investigation by narcotics investigators, who had documented several of his transactions and were planning another drug buy from him that evening.

Thompson was arrested several days later. Police found him with 106 wax paper packets matching those found near Mulhern’s body, a number of pills containing Alprazolam, fentanyl or oxycodone, and marijiuana.

In an interview with police, he admitted selling what he had believed to be heroin and Xanax to Mulhern on the day the victim died.

Police later found a loaded Glock 23 handgun inside the 2003 Crown Victoria sedan Thompson drove during his drug-selling excursions. Thompson was on parole for previous drug-dealing and firearms charges, and was prohibited from possessing guns, said Deputy District Attorney Thomas C. Gannon, who prosecuted the case.

The sentence was the result of a plea agreement negotiated between Gannon and defense attorney Harry J. Cooper.

Judge Rea B. Boylan accepted the terms of the agreement and imposed the sentence, which included a consecutive five years of probation for delivery of fentanyl.

The case was investigated by the Bristol Township, Falls Township and Bristol Borough Police Departments, as well as the Bucks County Detectives.

Contact: Thomas C. Gannon, 215.348.6461, tcgannon@buckscounty.org