A newly unsealed search warrant reveals a Utah detective’s suspicions that Kouri Richins’ mother may have been involved in planning the death of Richins’ husband, Eric.

Kouri Richins is accused of lacing a Moscow Mule she made for her husband with five times the lethal amount of fentanyl in March 2022, as Crime Online has reported. Afterward, she wrote a children’s book about coping with the sudden loss of a parent. Prior to her husband’s death, she tried to change his life insurance beneficiaries to her.

The search warrant contains information related to Kouri Richins’ mother, Lisa Darden. According to the document, Darden was involved with a woman who died unexpectedly in April 2006, KUTV reported. An autopsy report revealed taht the woman died from an overdose of oxycodone.

“Further investigation showed that Lisa Darden had been named as the beneficiary of her partner’s estate a short time before her death,” the document said. “The female did have current prescriptions for oxycodone and reportedly struggled with abusing her meds.”

“She 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.”

According to KSTU, the detective noted finding conversations on Kouri Richins’ phone in which her mother showed “disdain for Eric.”

“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,” the detective wrote.

Darden has not been charged in the deaths of either Eric Richins or her partner. Kouri Richins’ attorney, Skye Lazaro, issued a statement saying the death of Darden’s partner is “hardly suspicious.”

“The fact that Ms. Darden was the beneficiary of her romantic partner’s life insurance policy is also not unique,” Lazaro said. “It only demonstrates that her circumstances are no different than most families in America. To suggest otherwise is nothing more than a baseless conspiracy theory.”

Greg Skordas, a spokesperson for Eric Richins’ family, said that “nothing about this seems really surprising because we always felt that Kouri’s mother was in some way involved in this.”

“I think what the public can be assured of is that law enforcement and investigators in this case left no stone unturned, that they went very very deep” he said.

Prosecutors have said that Richins wrote a letter to her mother — the so-called “Walk the Dog” letter — in which she instructed her mother to tell her brother what to say to investigators. Richins later said the letter was part another book she was writing and tried to get the case against her dismissed based on the accusations of witness tampering.

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[Featured image: FILE – Kouri Richins. (AP Photo/Rick Bowmer, Pool, File)]