Ron Lafferty, 78, was convicted of killing his sister-in-law Brenda Lafferty and 15-month-old daughter Erica Lafferty

Irish American Ron Lafferty, who was found guilty of murdering his sister-in-law Brenda Lafferty and her baby daughter Erica in 1984, has died of natural causes before he was set to be placed before a firing squad for his crimes.

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The Salt Lake Tribune reports that 78-year-old Lafferty died of natural causes at Utah State Prison on Monday, November 11 after spending 34 years on death row. While an execution date had not yet been set, it looked to be likely coming as he lost a federal appeal in August.

Ron Lafferty, along with his brother Daniel, were both found guilty of murdering Brenda and her baby daughter. According to the Salt Lake Tribune, the Lafferty brothers had been excommunicated from The Church of Jesus Christ of Latter-day Saints and subsequently joined a polygamous cult called School of Prophets.

Ron Lafferty said he received a revelation from God ordering him to remove four people, including Brenda and her daughter, “in rapid succession,” a revelation that he shared with his cult, including his brother Dan.

On July 24,984, the Lafferty brothers set out with 23-year-old Charles “Chip” Carnes and 24-year-old Richard “Ricky” Knapp to commit the four murders, but ultimately ended up killing just Brenda and her daughter.

Publiée par Brenda Wright Lafferty Memorial sur Jeudi 11 janvier 2018

Following his conviction, Lafferty had chosen death by firing squad. The Salt Lake Tribune writes: “The Utah Legislature ended this execution option in 2004, except for inmates who had already been sentenced to die and had selected the method. Then, in 2015, the Legislature added firing squads again, but only if courts determine Utah does not have the cocktail of drugs needed to execute an inmate by lethal injection.”

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Therese Michelle Day, one of Lafferty's lawyers, said in a statement following Lafferty's death: "Mr. Lafferty believed his incarceration and conviction were the result of a conspiracy between the state, the Church, and unseen spiritual forces, including the spirit of the trial judge’s deceased father, among others. He believed that all of his attorneys were working against him, and that one attorney was his reincarnated sister who later became possessed by an evil spirit. A person suffering from this level of mental illness and delusional thinking is not competent to assist his counsel throughout his legal proceedings.

"Through it all, Mr. Lafferty himself never believed that he was mentally ill or incompetent. One expert said that if he was guilty of faking anything, he was guilty of pretending to be normal when he was not. Mr. Lafferty, like other mentally ill prisoners, was not treated for his mental illness as he should have been."

Utah’s Attorney General Sean Reyes said in a statement after Lafferty’s death: "The State of Utah has labored for decades to provide justice for Brenda and Erica Lafferty, who were brutally murdered by Ron and Dan Lafferty. That the wheels of justice turn so slowly in cases like this is cruel and tragic.

“Now that Mr. Lafferty is facing his Maker, perhaps ultimate justice will be realized and there will finally be some closure for the family of the victims."

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Sharon Weeks, Brenda Lafferty's older sister, told ABC 4 Utah that her family is "grateful" for Lafferty's death. 

"We feel like it’s just as well that he passed on his own," Weeks said, adding, “I absolutely felt a huge amount of relief when I heard the news that he had passed, because I preferred that he passed peacefully than have to go through what all of us were going to have to go through.”

In September, ABC 4 Utah shared this report on Ron Lafferty's case:

Brenda Lafferty and her 15-month-old daughter Erica were murdered by her brother-in-law Ron Lafferty in 1984.Brenda Wright Lafferty Memorial, Facebook