The mother of a Utah grief author accused of spiking her husband's drink with a fatal dose of fentanyl may have had a role in the death, according to investigators.
A detective with the Summit County Sheriff's Office also said that Kouri Richins' mother, Lisa Darden, is connected to the "suspicious overdose" death of Darden's former partner in 2006.
Darden has not been charged with any crime. She could not be reached for comment at phone numbers listed for her.
The details were revealed in a recently unsealed search warrant affidavit by a detective investigating the March 4, 2022, death of Eric Richins. He was found dead in his Kamas, Utah, home after he and his wife celebrated her closing on a home for her business, authorities have said.
A medical examiner said that Eric Richins had five times the lethal dose of fentanyl in his system and that it was “illicit” and not medical grade.
The search warrant affidavit said that as investigators interviewed people close to the couple, they learned that in April 2006, Darden's partner died unexpectedly.
The partner was a woman "with whom she was having a romantic relationship" and lived with, according to the document.
An autopsy showed that the woman's "immediate cause of death was a drug poisoning from an overdose of oxycodone," the document said.
Further investigation showed that Darden had been named as the beneficiary of the woman's estate "a short time before her death," it said.
The detective wrote in the document that the woman did have prescriptions for oxycodone and reportedly struggled with abusing her medication.
"She, however, was not in a state of recovery from addiction at the time of her death," the detective wrote. "Based on my training and experience, this would likely rule out the possibility of an accidental overdose."
The affidavit went on to say that investigators learned that Darden was at the Richinses' home the night they celebrated Kouri Richins' business deal. They also found conversations between Darden and Kouri Richins in which Darden expressed her "disdain" for her son-in-law, according to the affidavit.
The detective wrote that "based on Lisa Darden's proximity to her partner's suspicious overdose death, and her relationship with Kouri, it is possible she was involved in planning and orchestrating Eric's death."
Kouri Richins' attorney, Skye Lazaro, slammed the allegations. Lazaro is not representing Darden.
She said that Darden's partner died of an alleged opioid addiction and that anything that suggests otherwise is "a baseless conspiracy theory."
"Summit County is well aware that opioid addiction and fentanyl overdose is a rampant problem throughout the country," Lazaro said in an emailed statement Tuesday. "The fact that Ms. Darden’s significant other was one of the millions that suffered from, and ultimately succumbed to, opioid addiction is hardly 'suspicious.' It is tragic, and unfortunately, quite common."
She continued: "The fact that Ms. Darden was the beneficiary of her romantic partner’s life insurance policy is also not unique. It only demonstrates that her circumstances are no different than most families in America."
Kouri Richins was arrested last year on charges of aggravated murder and three counts of possession of a controlled substance with intent to distribute.
She has denied the allegations and is in custody awaiting trial.