Apr. 7—Aaron Charles Henning, a 45-year-old Marysville man who had been charged with murder for the poisoning and in-custody death of Matthew Perez in 2022, pleaded no contest on Wednesday to multiple charges and now faces multiple years in prison, the Yuba County District Attorney's Office said Friday.

On Dec. 8, 2022, Yuba County District Attorney Clint Curry filed a murder charge against Henning after an incident at the jail on Nov. 2, 2022. The Yuba County Jail inmate also was connected to the fentanyl poisoning of two other inmates, Curry said.

Henning pleaded no contest on Wednesday to multiple charges, including involuntary manslaughter, for the fentanyl poisoning and in-custody death of Perez on Nov. 2, 2022, as well as the poisoning of the other inmates. He is scheduled to be sentenced on May 1 and will face an agreed upon sentence of 12 years and 4 months in state prison, Curry said.

According to the Yuba County District Attorney's Office, agents from the Yuba-Sutter Narcotic and Gang Enforcement Team arrested Henning for possessing fentanyl for sale on Oct. 26, 2022. During that arrest, agents reportedly seized over an ounce of fentanyl and he was booked into Yuba County Jail.

On Nov. 2, 2022, Perez was pronounced dead at Adventist Health/Rideout Hospital in Marysville after correctional officers at the jail were "alerted of an inmate in distress," officials from the Yuba County Sheriff's Office previously said. The officers provided emergency medical treatment until paramedics arrived and multiple life-saving efforts were made, including repeated doses of Narcan, which can reverse the deadly effects of fentanyl, officials previously said.

"Henning managed to conceal and smuggle an additional half ounce of fentanyl into the jail. On November 2, 2022, Yuba County inmate Mathew Perez became unresponsive and died despite life-saving measures by jail staff," the Yuba County District Attorney's Office said. "The next day, two additional inmates lost consciousness from fentanyl poisoning but were revived by medical staff. An autopsy determined Perez died from fentanyl poisoning."

According to the Yuba County District Attorney's Office, sheriff's detectives "watched hours of video surveillance and conducted dozens of interviews to try to determine who smuggled and then distributed the fentanyl into the jail."

Officials said investigating crimes among inmates can sometimes be difficult because victims and witnesses will often refuse to cooperate.

"Henning admitted bringing the fentanyl into the jail, but told detectives he used it all himself. Henning was not shy talking about the fentanyl crisis," the Yuba County District Attorney's Office said. "Henning admitted worrying about family members who use drugs, explaining how the stakes had risen 'ever since Biden opened up the gates of hell,' allowing 'safe passage' for fentanyl to be 'backpacked' into the United States from Mexico. Calling the synthetic opioid 'la muerte' and 'gray death,' Henning was unequivocal about the danger: 'It's killing people.'"

According to data provided by the Cato Institute, U.S. citizens in 2021 made up 86.3% of convicted fentanyl drug traffickers — about ten times greater than convictions of illegal immigrants for the same offense. In reporting conducted by David J. Bier for the institute, he wrote that fentanyl smuggling is "ultimately funded by U.S. consumers who pay for illicit opioids" — nearly 99% are U.S. citizens.

Despite ongoing political rhetoric, Bier said more than 90% of fentanyl seizures occur at legal crossing points or through interior vehicle checkpoints, not on illegal migration routes.

"The government exacerbated the problem by banning most legal cross border traffic in 2020 and 2021, accelerating a switch to fentanyl (the easiest‐to‐conceal drug)," Bier wrote in 2022. "During the travel restrictions, fentanyl seizures at ports quadrupled from fiscal year 2019 to 2021. Fentanyl went from a third of combined heroin and fentanyl seizures to over 90%. Annual deaths from fentanyl nearly doubled from 2019 to 2021 after the government banned most travel (and asylum)."

According to data from the U.S. Sentencing Commission, fentanyl is primarily trafficked by U.S. citizens.

The U.S. Drug Enforcement Agency reported that criminal organizations "exploit major highway routes for transportation, and the most common method employed involves smuggling illicit drugs through U.S. (ports of entry) in passenger vehicles with concealed compartments or commingled with legitimate goods on tractor-trailers."

In May 2022, several government agencies told Congress that hard drugs come through U.S. ports of entry.

"During the early days of the pandemic, the Trump administration drastically restricted legal travel to the United States, banning nonessential travel through land ports of entry from Mexico in particular in late‐March 2020," Bier said. "Because there were fewer opportunities to traffic drugs at ports of entry, traffickers switched to trafficking more fentanyl. Because fentanyl is at least 50 times more potent per pound than heroin and other drugs­­, smugglers need fewer trips to supply the same market. ... From October 2018 to February 2020, about a third of fentanyl and heroin seizures at southwest ports of entry were fentanyl with no clear upward trend. By the time the travel restrictions were ended (at least for vaccinated travelers) in January 2022, over 90% of heroin‐fentanyl seizures were fentanyl. Unfortunately, the market shift has continued. The absolute amount of fentanyl being seized quadrupled."

The Yuba County District Attorney's Office said as part of Henning's plea agreement, he admitted to smuggling and distributing fentanyl into the Yuba County Jail and furnishing it to the three men who were poisoned, including Perez.

"Thank you to the jail staff who worked to save these men and to the detectives who quietly worked to put the pieces of this puzzle together," Yuba County District Attorney's Office said. "Fentanyl is a powerful synthetic opioid that is being sold on the street, often disguised as hydrocodone or Xanax or mixed into street drugs such as methamphetamine. A person who gives another person a lethal dose of fentanyl can be charged with murder, and in Yuba County we will do our best to hold those accountable who knowingly distribute 'pills that can kill.'"