United States Drug Enforcement Administration

SAN DIEGO – Jonathan Tyler Gauthier, a prolific fentanyl dealer who kept selling the deadly drug despite the fatal overdoses of two customers within a four-month span, was sentenced in federal court today to 30 years in prison.

According to the government’s sentencing memorandum, Gauthier sold the fentanyl that killed 24-year-old Sam Guest in September 2022 and 27-year-old Jesse White in December 2022. Gauthier continued selling fentanyl even after those deaths. As part of his February 2025 plea agreement, Gauthier admitted that the fentanyl he distributed caused their deaths.

Just before handing down the sentence, U.S. District Judge Janis L. Sammartino told the defendant: “This is one of the most tragic cases I’ve had in my courtroom in a long time.” 

“This sentence is a resounding reminder that dealing deadly and dangerous drugs like fentanyl is not a victimless crime – two lives were lost, and countless others forever changed by one man’s choice to exploit the vulnerabilities of others,” said DEA Acting Special Agent in Charge Jacob Galvan. “We thank our partners for their assistance in bringing Gauthier to justice and prosecuting him to the fullest extent of the law. The DEA will continue to pursue and hold accountable those who choose to profit by peddling deadly drugs.”

“Even after two people lost their lives, the defendant kept pushing poison for profit,” said U.S. Attorney Adam Gordon. “This 30-year sentence sends a stark message: If you deal fentanyl and show no regard for the deadly consequences, you will be held fully accountable. No excuses. No second chances.”

“This sentencing reflects the serious consequences awaiting those who choose to flood our communities with deadly fentanyl,” said Shawn Gibson, special agent in charge of Homeland Security Investigations (HSI) in San Diego. “HSI remains fully committed to holding these individuals accountable and continue to work closely with our law enforcement partners within the Fentanyl Abatement and Suppression Team (FAST) to remove this deadly threat from our neighborhoods.”

Sam’s mother described him as kind-hearted and full of joy. “To know Sam was to love Sam,” she said. In the wake of her loss, she holds onto memories of his infectious smile, his laughter, and the warmth he brought to others. Sam is deeply missed by his family, friends, and coworkers, all of whom continue to mourn his loss.

Jesse’s family remembered him as someone with a heart of gold. He had a passion for college football, a love of history, and a deep devotion to his family. He brought light into the lives of those around him—his parents, siblings, grandparents, and friends. He was especially close to his young niece, with whom he had been planning a special trip to the zoo. Jesse died in the early morning hours of Christmas Eve. He had taken the week off from work to spend the holiday season with his loved ones.

In its sentencing memo, the government listed several reasons the defendant’s actions warranted the requested sentence:

· Gauthier knew the fentanyl he was selling was deadly. He had a long history of dealing the drug and was well aware of its dangers. He even acknowledged the potency of a specific batch he sold to Sam, texting him afterward, “Ur being careful.” Despite this awareness, he sold it anyway—with tragic and foreseeable results.

· Even after Sam’s fatal overdose, Gauthier kept dealing. He knew Sam had died from fentanyl he provided—referring to him as “my buddy” in texts—but continued selling the drug. Just three months later, he sold 10 fentanyl pills to Jesse, who died the next morning. This shows a chilling disregard for human life.

· Gauthier’s criminal record underscores his persistent drug activity. Despite prior convictions for robbery and narcotics offenses, including one just weeks after Sam’s death, he kept selling. Even after Jesse’s fatal overdose, he was caught in Las Vegas selling methamphetamine and offering other drugs to an undercover officer.

This case is being prosecuted by Assistant U.S. Attorney David Fawcett.

Special Agents and Task Force Officers with the Drug Enforcement Administration’s Overdose Response Team and the Fentanyl Abatement and Suppression Team (FAST) jointly led this investigation. 

The Overdose Response Team is an ongoing effort by the U.S. Attorney’s Office, the San Diego County District Attorney’s Office, the Drug Enforcement Administration, Homeland Security Investigations, the San Diego Police Department, the La Mesa Police Department, National Guard Counterdrug Task Force and the California Department of Health Care Services to investigate and prosecute the distribution of dangerous illegal drugs—fentanyl in particular—that result in overdose deaths. The Drug Enforcement Administration created the Overdose Response Team as a response to the increase in overdose deaths in San Diego County.

HSI San Diego FAST is a multiagency task force comprising state, local, and federal partners and was first established in August 2022 focusing on the disruption and dismantlement of criminal organizations that smuggle and distribute fentanyl within San Diego County. HSI’s FAST targets fentanyl smuggling and distribution networks to counter the rising overdose rate and decrease the availability and accessibility of fentanyl.

INVESTIGATING AGENCIES

U.S. Attorney's Office; Homeland Security Investigations; San Diego Police Department; California National Guard Counterdrug Task Force; California Department of Health Care Services; La Mesa Police Department; San Diego County District Attorney’s Office