Kouri Richins, 33, is facing charges of aggravated murder and three counts of drug possession with intent to distribute over the March 2022 death of her husband Eric Richins.
Ms Richins allegedly killed her husband of seven years and father of her children by slipping a lethal dose of fentanyl into a Moscow Mule he later drank.
Before her arrest earlier this year, Ms Richins self-published a children’s book about grief based on her children’s experiences after they lost their father.
Last week, the 33-year-old was charged with witness tampering after a letter was found in her cell in which she allegedly asked her brother to “falsely” testify that her husband died after ordering drugs and pills from Mexico.
But now, in a phone call to her mother, Ms Richins has claimed the incriminating letter was simply part of a fictional book she is writing about her stay in a Mexican prison, according to court documents.
“When I first got in here I was telling you how I was writing a book … those papers were not a letter to you guys, they were part of my freaking book … I was writing this fictional mystery book,” Ms Richins says in the call, according to a court filing.
“I go to Mexico and I’m like trying to find these drugs … I’m writing about Dad … like me and Dad went to Mexico to find these drugs … you can very much tell that the whole thing is very much a story … then I get in the Mexican prison … I said have Skye sneak me in some white strips because my teeth are getting yellow because all we do is drink coffee in the Mexican prison.”
In the jailhouse letter, Ms Richins told her mother to instruct her brother, Ronald Darden, to testify that her husband got fentanyl from Mexico.
“Here is what I’m thinking but you have to talk to Ronney,” Ms Richins wrote in the letter.
“A year prior to Eric’s death, Ronny was over watching football and Eric and Ronny were chatting about Mexico trips. Eric told Ronny he gets painkillers [and] fentanyl from Mexico.”
Ms Richins went on to write that Mr Darden “would probably have to testify to this but it’s super short not a lot to it”.
She also said in the letter Mr Darden could take some liberties with the narrative as long as he got the point across.
Prosecutors have previously said there is no evidence suggesting Mr Richins bought the fentanyl that killed him.
In a request to the court filed on Tuesday, prosecutors said Ms Richins’ motion about the letter “contains factual errors and legal misunderstandings, rendering it unpersuasive at best”.
Prosecutors have claimed that Ms Richins had previously tried to poison her husband after he consulted a divorce attorney on learning that his wife was $2m in debt.
Ms Richins had also reportedly taken out at least four life insurance policies on her husband before allegedly poisoning him.
Ms Richins has denied all the allegations against her.
If convicted, she faces between 25 years to life in prison.