Cover story, felony murder, fentanyl
November-December 2023

Fentanyl dealer sentenced to 45 years for felony murder

By John Gillespie
Criminal District Attorney in Wichita County

“This is the punishment verdict form that you will fill out, but it’s also something else,” Matt Shelton, an assistant criminal district attorney in Wichita County, told a recent jury. 

Quizzically, the jurors watched as Matt folded and twisted the jury form into a cone. He raised it to his mouth: “This is also your megaphone. With your verdict, you can say ‘Enough!’ to those who deal fentanyl in our community. And they are listening.”

            While watching Matt’s punishment closing, I reflected on a conversation from August 2022, a year before. Wichita Falls had been awash in fentanyl overdose deaths in the summer of 2022, one after another after another. All senseless. Many young. Often overdoses on one pill. Users thought they were getting street Percocet but were instead ingesting deadly fentanyl.

            To address the crisis, Sergeant Brian Sheehan, in charge of homicide investigations for the Wichita Falls Police Department (WFPD), and several narcotics officers met with me on a sweltering August day to pitch charging dealers with manslaughter.

            “Manslaughter is fine,” I told them, “but if you really want to get their attention, light them up for felony murder,” and I outlined why such a charge would fit. The officers liked that approach. With the strategy in place, WFPD Chief Manuel Borrego and I held a joint press conference to put dealers on notice and to implore parents to talk to their kids about fentanyl. In the months that followed, the WFPD announced the arrest of three fentanyl dealers for three separate murders where the pills they dealt could be traced to the fatal overdoses.

            Now, a year later, a jury had taken about an hour to convict one of those dealers, Jasinto Jimenez, of felony murder. Then, they took their megaphone and returned a 45-year sentence.

The murder of Andres Diaz

The events that led to the murder of Andres Diaz started on July 14, 2022, when the 21-year-old texted his friend Leigha Smith, asking if she wanted to hang out. Andres had struggled with substance abuse for years. Leigha, also 21, agreed to meet up, driving to his house to pick him up.

            Andres and Leigha chatted, deciding they wanted to get high. Andres had used coke earlier that week and he tried to contact his cocaine hook-up. That dealer didn’t answer. Leigha called her dealer, Jasinto Jimenez, who sold weed and “percs” (street Percocets), and they set up a deal. Pooling their money, Andres and Leigha came up with $80 for their hits.

            Leigha drove them to Jimenez’s house. In his driveway, Jimenez sold them two percs and some marijuana at $30 a perc and $20 for the marijuana. Leigha passed one of the percs to Andres. Then she drove to a 7-Eleven to buy cigarillos to roll blunts and a Gatorade, which she used to gulp down her perc. Andres then, fatefully, took the Gatorade bottle, crushed his perc, and snorted it. Next, they rolled blunts and smoked the marijuana.

            Jamming to music, Leigha drove them to a spillway at Lake Wichita. On the way, Andres fell asleep. With him sleeping, Leigha headed back to her house. Andres was snoring.  When she tried to wake him, he wouldn’t stir, so she rolled down the windows and left him snoring in the car. Leigha then went inside and watched a movie. During the night, she checked on Andres several times but could not wake him. At 5:00 a.m., she noticed his snoring had stopped. She ran inside to get her mom, who checked Andres with a stethoscope, but she could not detect a heartbeat. Leigha rushed Andres to the emergency room, where resuscitation attempts were futile. Andres was pronounced dead at 5:30 a.m.

Powerful evidence of knowledge

To apply felony murder to a fentanyl dealer, our office wanted the iron-clad ability to trace the lethal dose back to the dealer and overwhelming evidence of guilt. The investigation into Jasinto Jimenez developed powerful evidence of both.

            Under 19.02(b)(3) of the Texas Penal Code, felony murder requires that the defendant:

            1) while in the course of committing or attempting to commit a felony,

            2) commits an act clearly dangerous to human life that

            3) causes the death of another.

            Delivery of fentanyl is a felony under the Texas Controlled Substance Act.[1] Further, the evidence to prove causation and trace the fentanyl back to Jimenez was solid. Leigha was an eyewitness. She cooperated with law enforcement and provided her texts with Jimenez setting up the sale. While she was charged with manslaughter for her role, Leigha testified without a deal and without immunity.[2] She could connect the perc that killed her friend to Jimenez. Further, Jimenez had admitted in a jail call that he had sold them the lethal dose. The autopsy concluded Andres’s death was caused from the toxic effects of fentanyl.

            Importantly, the Jimenez investigation demonstrated strong evidence that he knew his actions were clearly dangerous to human life. Previously, Jimenez had emerged as a target of WFPD narcotics investigators. Investigators executed a search warrant on his residence on June 29, 2022, two weeks before Andres’s homicide. In the search, they found a pill under his bed, which testing revealed to be fentanyl.

             During an interview with investigators immediately following the execution of the June 29 search warrant, Jimenez admitted he knew the pill was fentanyl, but he initially denied dealing. “I wouldn’t deal fentanyl—that’s dangerous,” Jimenez declared. Then he started crying while discussing people he had heard of who died from fentanyl overdoses. Later, he finally confessed that he was dealing percs that he knew were fentanyl. Jimenez had no job and had not worked in a while. He purchased the percs for $10 a pop and could double or triple his money, selling them from $20–35 each.

            Jimenez’s admissions that he knew he was dealing fentanyl and he knew how dangerous it was were crucial evidence that he was committing acts clearly dangerous to human life. Notably, the Texas Court of Criminal Appeals has held that the underlying felony can also constitute the act clearly dangerous to human life in a felony murder prosecution.[3]

Strategy for jury selection on felony murder

For jury selection to be successful, the prosecution wanted jurors who were comfortable with applying felony murder, who could convict of murder without intent to kill, and who understood concurrent causation.

            I handled voir dire, taking the panel through the law on felony murder and providing examples. I asked a commitment question:  “If you believed the evidence established the elements for felony murder beyond a reasonable doubt, but there was no intent to kill, would you return a verdict of guilty?” This is a proper commitment question because panel members who were unwilling to convict without the defendant’s intent to kill were elevating the standard of proof above what Texas law requires. This exposed multiple bad panelists and set up successful challenges for cause.

            To illustrate how dealing fentanyl could be an act clearly dangerous to human life, I put up a photo of the Corner Drug Store in Burkburnett and my father, Joe Gillespie, a pharmacist. “My dad took his job very seriously,” I told them. “One story he always told was about two drugs that had similar names, one being a dangerous heart medicine. Once, Dad filled a prescription. After the customer picked it up, Dad had a nagging feeling. He rechecked the handwritten prescription and realized he had misread the doctor’s writing. Then he bolted from the pharmacy and rushed to the customer’s house. Dad had dispensed the wrong, dangerous heart drug by accident. Thankfully, he caught his error before the customer had taken any. Even though he was meticulous about his job as a pharmacist, he always feared how deadly such a mistake could be.”

            This story illuminated why Texas law utilizes licensed pharmacists to dispense drugs pursuant to prescriptions by doctors. I also discussed the quality control measures for drug manufacturers so people had confidence they were getting the proper dosage, helping establish why dealing street fentanyl without a prescription, not under a doctor’s care, and with no quality controls was an act clearly dangerous to human life.

            For causation, this case presented three concurrent “but for” causes: Jimenez for dealing fentanyl, Leigha for purchasing it and giving it to Andres, and Andres for snorting it. Section 6.04 of the Penal Code explains a person “is criminally responsible if the result would not have occurred but for his conduct, operating either alone or concurrently with another cause, unless the concurrent cause was clearly sufficient to produce the result and the conduct of the actor clearly insufficient.”

            To help the panel understand that legal mouthful, I used a photo of a Coke machine and asked what were the “but for” causes for a Coke to drop. A venire-member thought about it and answered:  1) put money in and 2) push the button.

            “If you put the money in and push the button, you are both ‘but for’ causes to the Coke dropping. But what if you have a child with you, and you put the money in but tell him to pick what he wants? In that situation, you and the child are both ‘but for’ causes acting concurrently.  If you put money in, but nobody pushes a button, a Coke won’t drop. Or if you push a button, but you don’t insert money, nothing happens. Both actions are operating together to cause a Coke to drop.”

            This hypothetical illustrated that while Andres was a “but for” cause in snorting the deadly perc, he would have no fentanyl to snort “but for” Leigha buying it and “but for” Jimenez dispensing it. Thus, there were three concurrent “but for” causes to Andres’s death that operated together. Like the Coke machine example, none of the “but for” causes were sufficient to cause the result operating alone.

Expert testimony is key

Fentanyl skyrockets past standard street drugs such as cocaine, meth, and even heroin in lethality.  For success at trial, ADA Shelton believed a jury needed to be educated about fentanyl’s unique and dangerous toxicity. Dr. Stacey Hail, who teaches emergency medicine at UT Southwestern and is a nationwide poison control and fentanyl expert, provided key testimony.

            Dr. Hail explained opiates, opioids, and synthetic opioids. Morphine has a baseline of 1 as to potency. Codeine, a weak opioid, is a 0.1. Oxycodone (the generic name for Percocet) has a potency between 1.5 and 3.5. Heroin measures a 2.5–5 potency. Astonishingly, fentanyl is 100–150 times more potent than morphine.

            While Dr. Hail agreed with the slogan “one pill can kill,” she testified that the most common fatal fentanyl overdose she sees is from a portion or fragment of one pill. She further explained that due to fentanyl’s potency, tiny changes in the dose render fentanyl incredibly lethal.           

            “Socrates said, ‘The dose makes the poison,’” Dr. Hail testified. “The higher the potency, the higher the lethality. Because fentanyl is such a potent opioid, that makes it so very dangerous.”

            Prescription fentanyl is produced by drug manufacturers with rigid quality controls and dispensed by pharmacists. In hospitals, doctors use prescription fentanyl for surgical procedures and pain management following surgery. But illicit fentanyl has no quality controls and often comes from Mexico or China.

            “Because there are no quality controls, a drug dealer has no idea the dose of fentanyl in any pill,” Dr. Hail said. Her testimony set up the prosecution’s argument that the act of dealing such an incredibly potent, toxic drug was clearly dangerous to human life. The jury agreed, convicting Jimenez of murder after only an hour of deliberations.

Punishment testimony shows dealers listen

Punishment evidence demonstrated that the murder charges against Jimenez impacted the availability of fentanyl in Wichita Falls. Narcotics investigator Andrew Schenk said that after the felony murder charges were announced, it became nearly impossible for his confidential informants to set up buys of percs, which were usually laced with fentanyl. “The dealers did not want to take the risk of murder charges,” Schenk testified.

            Sergeant Brian Sheehan also vouched for the impact on Wichita Falls. “Before we announced the fentanyl felony murder arrests, we were responding to at least one fatal overdose a month, sometimes more,” he testified. “After the arrests, that dropped way off.”

            Sheehan believed the drop was multi-causal, also including the education push in the community as well as the greater availability of Narcan, the fentanyl antidote. However, Sheehan identified the timing of the felony murder arrests as when the overdose deaths started to decrease.

            Referencing their testimony, ADA Shelton argued that the jury had more power than the President to impact fentanyl in this community by sending a message. He also emphasized the defendant’s depraved indifference to human life: “He knew how dangerous it was. You heard him say that. He knew he was dealing fentanyl. You heard him admit that too, just two weeks before. He showed a depraved indifference to human life by continuing to knowingly deal this poison in our community. Money was all he cared about.”

            After three hours of deliberations, the jury returned with a 45-year-sentence, which was significantly higher than the 25-year sentence the defense attorney had requested.

The new fentanyl murder law

In response to the fentanyl crisis, the Texas legislature amended the murder law to create a fentanyl-specific murder offense. Under new Penal Code §19.02(b)(4), a person commits an offense if he or she knowingly manufactures or delivers fentanyl and an individual dies as a result.

            While Wichita County had an acute crisis in our community and needed to use the tools we had in 2022 to respond, our case provides some important guidance on how to present a case under the new law:

Evidence, evidence, evidence. Like location in real estate, compelling evidence provides the key to success. Reserve murder charges for cases with powerful proof that clearly and indisputably traces the overdose to the fentanyl dealt by the defendant. If your proof is shaky, then opt for a lesser charge, such as delivery. Section 481.141 of the Health and Safety Code enhances delivery that caused death or serious bodily injury one degree; however, the enhancement is not available if a defendant is also being prosecuted under the new fentanyl murder law.[4]

Use an expert. A jury must understand that fentanyl is dramatically more toxic than standard street drugs. Dr. Hail was key in educating the jury on the unique danger: Fentanyl is 50–60 times more potent than heroin. The extreme danger justifies the murder charge to a jury.

Explain causation. Because these cases are likely to involve a drug-seeker or addict who purchased and ingested the illicit drug, a jury must understand Texas law on “but for” causation and concurrent causation. Criminally, Texas does not have a proportional responsibility law that exists in civil cases. It is critical to explain that while the user paid the ultimate price for his crime, the dealer is still a “but for” and concurrent cause and therefore still criminally liable.

Commit the jury on convicting with no intent to kill. Under either felony murder or the new fentanyl murder law, there is no requirement to prove intent to kill. Such evidence is unlikely to exist in these cases. Therefore, explain to the jury that there are various ways to prove murder, and some do not require intent to kill. Then commit the panel that if the evidence proved all the elements beyond a reasonable doubt, but there was no proof of intent to kill, they would convict. This is a valid commitment question, as those who refuse to convict cannot follow the law. Remind the jury at closing that each gave their word under oath that they would convict if the elements are proven, without intent to kill.

Consider charging fentanyl murder and felony murder as alternative paragraphs. Because it is unclear whether the new law in §19.02(b)(4) requires proof that the defendant knew he was delivering fentanyl (as opposed to illegal contraband in general), felony murder may provide another option for situations where the dealer hasn’t admitted he was dealing fentanyl. Many dealers may claim they are dealing Percocet, may deny they are dealing fentanyl, or may be silent. The proof will often involve texts about “percs.” Percocet is oxycodone, which is in Penalty Group 1, while fentanyl is in Penalty Group 1-B. Felony murder would let the State allege that the defendant “attempted to commit” the felony of delivering oxycodone and/or fentanyl. It would also permit the allegation that not knowing what he is dealing is itself an act clearly dangerous to human life. If a dealer who is not a pharmacist is dealing a drug with no quality controls not pursuant to a doctor’s prescription, that act would be clearly dangerous to human life, regardless of whether the dealer knew he was actually dealing fentanyl. The alternatives to committing murder do not constitute separate offenses; thus, they may be alleged as alternative paragraphs and a jury can still return a general verdict on murder.[5] The smartest practice will often be to allege alternative paragraphs with felony murder and the new fentanyl murder.

Spread the community danger at punishment.  Because a victim likely was a drug-seeker or addict, expand the community danger: “This defendant did not care who ended up with the fentanyl so long as he got his money. Sure, it was Andres Diaz who ingested it and died, but this defendant didn’t know where the perc was going. It could have been to any college student in our community, any high school student, any junior high student, or even, God forbid, an elementary school student. Dealing those pills like he did was playing Russian roulette with so many lives. And the defendant showed a depraved indifference to them all.” Jurors will think of their kids and grandkids and ratchet up the punishment number. 

We must do something

 Our case demonstrated that juries are sick of the fentanyl death epidemic and are eager to hold accountable those who peddle this poison in our communities. The extreme toxicity of fentanyl justifies examining these cases as homicides. 

            While aggressive investigation and prosecution is not a magic solution to the fentanyl crisis, law enforcement plays an important part in a multi-pronged, community-wide response.

            “The felony murder charges have definitely had an impact,” Sergeant Sheehan said. “It’s the only time in my career when I’ve seen something have that drastic an impact. We’ve significantly increased the cost of doing business to street-level dealers. Now, the jury has backed us up. I believe this 45-year murder sentence will save lots of lives in our community.” i


[1]  Health & Safety Code §481.1123.

[2]  Charges are still pending against Leigha for manslaughter, and she is still in custody.

[3]  See Johnson v. State, 4 S.W.3d 254 (Tex. Crim. App. 1990) (upholding a conviction for felony murder where the underlying felony was injury to a child and the acts clearly dangerous to human life were the same acts that comprised the injury to a child felony).

[4]   See Health & Safety Code §481.141 (d).

[5]  See, e.g., Bundy v. Texas, 280 S.W.3d 425 (Tex. App.—Fort Worth 2009, pet. ref’d) (explaining jury unanimity is not required as to alternative means of committing murder with different mental states).