New ’48 Hours’ investigation reveals how Maria Muñoz became a key witness in her own murder

A Texas mother’s own words became a key part of testimony in her murder trial — helping to convince a jury she was killed by her husband, according to a new “48 Hours” investigation.

Joel Pellot is serving life in prison after he was convicted last March of the September 2020 murder of his 31-year-old wife and the mother to his two young sons, Maria Eugenia Muñoz.

Muñoz’s death appeared to be a suicide by pill overdose at first glance, but pages and pages of her journal entries indicate she didn’t have any suicidal thoughts.

Instead, the journals revealed a woman looking forward to moving on after the husband she loved deeply had cheated, the CBS show revealed.

Pellot, a nurse anesthetist, called 911 in the early morning hours of Sept. 22, 2020, to report that his wife of 10 years was unresponsive and may have overdosed on pills.

But right away, police were suspicious of Pellot’s behavior and explanation of the events that led to his wife’s death. The man was sweating profusely and couldn’t answer simple questions about when and how he found his Muñoz.

They also found a syringe wrapper on the floor and a needle catheter on the stairs.

Investigators soon learned that he had been seeing a woman from work named Janet Arredondo for the past two years and was living with her at the time.

He told cops that Muñoz knew about their relationship “for a long while,” according to “48 Hours.”

Then they learned that the medical examiner found no pill residue in her stomach but did find a tiny puncture mark on her right elbow crease.

The medical examiner determined that Muñoz died from a mixed drug intoxication but she ruled out suicide after looking through the young mother’s journal entries and speaking with her friends.

The day before she died, Muñoz wrote: “What is it that I want? #1 Move forward,” according to the news show.

Pellot’s former boss, anesthesiologist Dr. John Huntsinger, learned of the autopsy results and called the head detective on the case to tell him he was suspicious. He advised investigators to do a full toxicology screening.

Four months later, the results came back and revealed Muñoz died from a fatal combination of morphine, Demerol, Versed, propofol, ketamine, lidocaine, and Narcan — almost all drugs typically used in surgery and ones that a nurse anesthetist would have access to.

Propofol is the one drug that was in her system that is only administered by injection.

There was so much of it in her system that it would have caused her to stop breathing, according to Huntsinger and the toxicology report.

It also was one of the drugs Pellot would take home from work to use recreationally, according to Arredondo, his mistress, “48 Hours” reported.

Prosecutors believe Pellot first slipped some of the drugs into Muñoz’s drink to sedate her and once she was out of it, he injected the propofol into her arm and waited to call 911 so that first responders wouldn’t be able to resuscitate her.

Days before her death, Muñoz and Pellot got into an argument after she spotted his car parked outside Arredondo’s house. Pellot berated his wife, cursed at her and punched the windshield, smashing it.

The next morning, Muñoz texted her husband about hiring a divorce lawyer and he responded: “We can do this with minimal lawyer intervention. It’s too much money.”

But he later sent her an email asking to sit down to talk without arguing in “a heart-to-heart.”

“I am so sad I am hurting inside,” he wrote in the email.

The couple agreed to meet on Monday night. Muñoz died early the next morning.