PARK CITY, Utah (AP) — Detectives on Monday described in court how they zeroed in on a Utah mother known for penning a children’s book about grief as the main suspect in her husband’s fatal poisoning. The multiday hearing will determine whether prosecutors have enough evidence against her to proceed with a trial.

Kouri Richins, 34, faces several felony charges for allegedly killing her husband with a lethal dose of fentanyl in March 2022 at their home in a small mountain town near Park City. Prosecutors say she slipped five times the lethal dose of the synthetic opioid into a Moscow mule cocktail that Eric Richins, 39, drank.

Additional charges filed in March accuse her of an earlier attempt to kill her husband with a spiked sandwich on Valentine’s Day. She has been adamant in maintaining she is innocent.

Detective Jeff O’Driscoll with the Summit County Sheriff’s Office was called to the stand Monday to describe his interactions with the state’s key witness, a housekeeper who claims to have sold fentanyl to Kouri Richins on three occasions. He said police first linked housekeeper Carmen Lauber to Kouri Richins through a series of text messages and later arrested Lauber, saying drugs and other illegal items were found at her home.

Lauber, 52, originally denied any knowledge of how Eric Richins died, but she later opened up in an interview with O’Driscoll after he told her the drug charges against her might be reduced or eliminated in exchange for helpful information, the detective said. The housekeeper “went back and forth on what happened, what didn’t happen and in what order things happened,” O’Driscoll explained in court.

He said Lauber told him she had sold Kouri Richins up to 90 blue-green fentanyl pills, and her supplier later confirmed to detectives that he had sold her the fentanyl she requested. Officers did not find any fentanyl pills in the Richins home, the detective said.

Lauber has received a letter of immunity from the U.S. Attorney’s Office and is not currently in custody, O’Driscoll said. She is among the witnesses who could be called to testify later in the hearing or during a possible trial.

Other witnesses may include relatives of the defendant and her late husband, and friends of Eric Richins who have recounted phone conversations from the day prosecutors say he was first poisoned by his wife of nine years.

In the months before her arrest in May 2023, the Utah mother of three self-published the children’s book “Are You with Me?” about a father with angel wings watching over his young son after passing away. The book could eventually play a key role for prosecutors in framing Eric Richins’ death as a calculated killing with an elaborate cover-up attempt. Prosecutors have accused Kouri Richins of making secret financial arrangements and buying the illegal drug as her husband began to harbor suspicions about her.

Utah state Judge Richard Mrazik is expected to decide as early as Tuesday whether the state has presented sufficient evidence to go forward with a trial.

Mrazik had delayed the hearing in May after prosecutors said they would need three consecutive days to present their evidence. The case was further slowed when Kouri Richins’ team of private attorneys withdrew from representing her. The judge determined she was unable to continue paying for private representation, and he appointed public defenders Wendy Lewis and Kathy Nester to take over her case.

The two attorneys used the first day of the hearing to build upon arguments presented by Kouri Richins’ former lead attorney, Skye Lazaro. They insinuated that the housekeeper Lauber had motivation to lie as she sought leniency in the face of drug charges.

Lazaro also argued that Eric Richins’ sisters had a clear bias against her former client amid a battle over his estate and a concurrent assault case. Similar arguments could arise if family members are called to the stand.

A petition filed by the victim’s sister, Katie Richins, alleges Kouri Richins had financial motives for killing her husband as prosecutors say she had opened life insurance policies totaling nearly $2 million without his knowledge and mistakenly believed she would inherit his estate under terms of their prenuptial agreement.

Court records indicate Eric Richins had consulted an attorney in October 2020 to discuss the possibility of filing for divorce and to quietly cut his wife out of his will. Forensic accountant Brooke Karrington⁠ said transcripts from that meeting indicate Eric Richins knew his wife was making major financial decisions without consulting him, but he never went through with ending the marriage.

In May, Kouri Richins was found guilty on misdemeanor charges of assaulting her other sister-in-law shortly after her husband’s death. Amy Richins told the judge that Kouri Richins had punched her in the face during an argument over access to her brother’s safe.

In addition to aggravated murder, assault and drug charges, Kouri Richins has been charged with mortgage fraud, forgery and insurance fraud for allegedly forging loan applications and fraudulently claiming insurance benefits after her husband’s death.