From the State’s Attorney:
MONTHS-LONG UNDERCOVER INVESTIGATION LEADS TO ARREST AND DETENTION OF ALLEGED FENTANYL TRAFFICKER
McHenry County State’s Attorney Randi L. Freese announces that the Honorable Judge Cynthia Lamb has ordered Aaron D. Johnson, 30, of Downers Grove, Illinois, detained pending trial following his arrest on multiple felony narcotics charges stemming from a lengthy undercover investigation conducted by the McHenry County Sheriff’s Office Narcotics Task Force.
The investigation spanned several months and involved an undercover officer who conducted multiple controlled purchases of illicit narcotics from Johnson.
Between May and July 2026, investigators allegedly purchased significant quantities of f
- entanyl,
- heroin,
- cocaine, and
- counterfeit M30 pills containing fentanyl
from him.
During the investigation, law enforcement conducted several controlled buys from Johnson and recovered
- over thirty grams of fentanyl mixed with cocaine and heroin,
- over sixty grams of fentanyl mixed with cocaine, and
- almost 300 counterfeit M30 fentanyl pills.
Investigators later arranged a larger narcotics transaction in which Johnson allegedly agreed to sell five ounces of cocaine, one ounce of heroin, and 500 counterfeit M30 pills. Before that transaction could occur, members of the McHenry County Sheriff’s Office Narcotics Task Force executed an arrest warrant on July 16, 2026, in Crystal Lake.
At the time of his arrest, investigators recovered on Johnson’s person
- approximately forty grams of a substance containing cocaine and fentanyl,
- almost thirty grams of a substance containing heroin n total, officers recovered approximately 227 grams of fentanyl during the arrest.and fentanyl, and
- approximately 500 counterfeit M30 pills containing fentanyl.
In total, officers recovered approximately 227 grams of fentanyl during the arrest.
Immediately following the arrest, investigators executed a search warrant at Johnson’s Crystal Lake apartment, where his pregnant girlfriend and her 10-year-old son were present.
During the search, investigators recovered additional heroin, fentanyl, counterfeit M30 pills, narcotics packaging materials, scales, baggies, mixing equipment, and a full-face respirator commonly used to protect against airborne fentanyl exposure while processing narcotics.
Investigators also recovered a loaded firearm from inside the residence.
The firearm was unsecured and located in a bedroom closet.
Authorities further alleged that narcotics processing equipment and controlled substances were located throughout the kitchen area within easy reach of children inside the home.
According to evidence presented during the detention hearing, fentanyl is frequently mixed with other illicit drugs to increase potency, dramatically increasing the risk of fatal overdose.
Fentanyl is approximately 100 times more potent than morphine, and as little as two milligrams can be lethal.
Counterfeit M30 pills often contain unpredictable amounts of fentanyl, making even a single pill potentially deadly.
Evidence presented during the hearing showed that Johnson regularly traveled to Arizona, maintained contacts in Arizona and Mexico, had a criminal history that included prior flight and escape-related offenses, and had allegedly used fraudulent identities to obtain rental properties, making his whereabouts more difficult to determine.
“This man didn’t just bring illegal drugs into McHenry County.
“He brought death to our county,” Assistant State’s Attorney Garrett Miller argued at the hearing.
The Court granted the State’s Petition to Deny Pretrial Release after finding that Johnson posed a significant threat to the safety of the community and presented a serious risk of willful flight.
State’s Attorney Freese praised the extensive investigation, stating: “This case demonstrates the relentless commitment our Sheriff’s Office Narcotics Task Force has to removing this deadly poison from our communities before it claims more lives.
“The quantities of fentanyl recovered during this investigation had the potential to cause immeasurable harm.”
The McHenry County State’s Attorney’s Office commends the McHenry County Sheriff’s Office Narcotics Task Force and all participating law enforcement agencies for their months-long investigation and continued efforts to combat the distribution of fentanyl and other dangerous controlled substances throughout McHenry County.
Johnson’s next court appearance is scheduled for July 31, 2026, in Courtroom 302.
Members of the public are reminded that a criminal complaint contains only charges and is not proof of the defendant’s guilt. The defendant is presumed innocent and entitled to a fair trial, at which the State bears the burden of proving guilt beyond a reasonable doubt
