5 chilling details about Denise Hallowell's brutal murder

The Dateline: Secrets Uncovered episode Horror at the Lake examines the murder of Denise Hallowell and the conviction of her adoptive son Carlos Hallowell, in the case. Originally aired on November 5, 2021, the episode will be broadcast again today, August 13, on Oxygen at 4 PM ET.

In July 2019, the lakeside town of Inverness, Florida, was shaken by the news of the brutal killing of schoolteacher Denise Hallowell. Her 17-year-old adoptive son, Carlos, called 911 to report the crime. He claimed to have discovered Denise dead in her bedroom. When the police responded to the call, they found Denise had been killed by an ax blow to the back of her head.

---

Denise Hallowell's brutal murder: 5 details from the case

1) Denise Hallowell's body was discovered by her son, Carlos

Denise Hallowell's murder is explored on Dateline: Secrets Uncovered (Image via Getty)

On July 13, 2019, the small town of Inverness in Florida was shaken with the news of the brutal murder of fifty-seven-year-old special education teacher Denise Hallowell. She was discovered dead by her 17-year-old adoptive son, Carlos, who had called 911.

Denise Hallowell had adopted Carlos from Guatemala when he was just four years old, raising him on her own. In his initial statement to the police, Carlos said he was woken at night by the sound of the dogs barking and went to check on his mother. It was then that he discovered that his mother had been murdered. But as detectives dug deeper, they began to notice inconsistencies in his story, and their suspicions started to grow.

---

2) A strained relationship and troubled past

During his interrogation, Carlos admitted that his relationship with his adoptive mother had grown strained over the years, with frequent clashes over his drinking and drug use. Denise, who had always encouraged him to aim high, wanted him to attend a four-year university and build a stable career. Carlos, however, had his sights set on attending a technical college instead.

He also claimed that life at home was far from perfect, alleging that Denise had been physically abusive toward him and toward Angel, another boy she had adopted from Honduras. According to NBC Miami, Denise was arrested in 2015 for alleged abuse of Angel, but the charges were dropped due to insufficient evidence.

---

3) The night of the murder

The night of the killing, prosecutors alleged that Carlos entered her bedroom and struck her in the skull, killing her instantly. While Carlos later admitted to killing his mother, he told investigators, as reported by The Chronicle, that he "blacked out" during the attack.

However, the police concluded that the murder was premeditated because Carlos had removed the home security cameras and discarded Denise's phone before he killed her. Three cameras and the phone were later recovered from the lake by divers, according to Oxygen.

---

4) A motive behind the crime

At first, Carlos insisted he had nothing to do with his mother's death. However, when investigators delved deeper into the case, the truth began to emerge. Confronted by evidence, he eventually admitted to killing Denise — though he claimed it was a spur-of-the-moment act, not something he had planned. Prosecutors saw it differently.

They argued the murder was deliberate and driven, at least in part, by Carlos's desire to get his hands on his mother's property and assets.

---

5) The trial and sentencing of Carlos Hallowell

Since Carlos was a minor at the time of the murder, he avoided a death sentence. However, he was convicted of first-degree murder, and the Citrus County Circuit Court Judge Richard Howard agreed with the prosecution's assessment of the crime and motive behind it. He also stated that Carlos met 16 out of 20 criteria for psychopathy.

Carlos was ultimately sentenced to life in prison without the possibility of parole. Addressing his late mother in court, he said:

"Mom, I'm so very sorry. Words can't describe how I feel right now, how much I miss you… I love you so much," Carlos said in court, as per the Chronicle.

According to state prison records, Carlos is now serving his sentence at Holmes Correctional Institution in Florida.

---

Catch tonight's Dateline: Secrets Uncovered episode for more about the case.