20-year-old admits ‘voices’ told him to kill a Tri-Cities neighbor mowing the lawn

A 20-year-old Kennewick man may spend the next 30 years in prison after admitting to stabbing and killing his neighbor as he mowed the lawn.

Hector R. Munguia told a judge Wednesday that he could have ignored the hallucinations that pushed him to stab and kill his neighbor on April 22, 2022.

He pleaded guilty to first-degree murder. His sentencing hearing has yet to be scheduled.

While he has agreed to the crime, the amount of time he’s facing in prison remains under debate. The sentencing range will depend on whether crimes he committed as a juvenile will count toward his sentencing range.

One of those convictions was for second-degree assault after stabbing a woman getting out of her car in Kennewick.

If the juvenile crimes count under Washington law, he will face about 22 to 30 years in a state prison. If not, he will face 20 to more than 26 years.

Prosecutors plan to ask for a 30-year sentence, and his defense attorney intends to request less time.

Munguia has been in the Benton County jail since shortly after he killed Zale Underwood, 70.

Munguia allegedly ran home after the stabbing and was taken to the sheriff’s office by his mother.

After he was booked into jail, he reported that he suffered from hallucinations that he called “demons” who urged him to hurt people.

An Eastern State Hospital mental evaluation found he suffers from an unspecified schizophrenia spectrum and other psychotic disorder, as well as cannabis and alcohol use disorders.

While they said his heavy use of cannabis appeared to have led to hallucinations in the past, neither Benton County officers nor Eastern State Hospital officials found he appeared to be reacting to internal stimuli, according to the reports.

He was found competent to stand trial but instead pleaded guilty.

April 2022 stabbing

Underwood was mowing his lawn in the 1100 block of Gum Street neighborhood where he and his family had lived since the early ‘60s on the spring afternoon when he was approached by Munguia.

The young man later told investigators that he thought about killing Underwood for a few minutes before stabbing him.

“When asked if he knew it was wrong, Hector stated he did, but he didn’t care,” according to court documents.

He stabbed him a several times before running away.

Benton County deputies were initially called to Underwood’s home by a family member who said he was bleeding heavily, according to dispatch reports at the time.

By the time police arrived, Underwood had died. Police found a bloody palm print on the fence separating the Underwood’s and Munguia’s property, according to court records.

Benton County deputies and Kennewick police officers surrounded the area and began searching for a suspect but found no one.

2019 stabbing

The April 2022 attack was not the first time Munguia was accused of attacking someone with seemingly little reason, according to court documents.

Three years ago, he was convicted of an equally mysterious stabbing of another 70-year-old woman just a mile from where Underwood was killed.

Munguia was 16 at the time.

That attack happened just before 5 p.m. on Dec. 4, 2019, when he approached Lydia Cassaway as she was getting out of her car at an apartment building on South Washington Street.

He asked her for money, but Cassaway told him she didn’t carry any cash. He told her that he was hungry.

“He then asked her if he could tell her something. She said, ‘OK,” and his response was to poke her with something in back,” Kennewick police wrote in a report at the time.

She screamed and the teen ran off. Then, she started feeling pain in her back and noticed she was bleeding, but it was only after she ran to a safe spot that she realized she had been stabbed.

She went to the fourth floor of the apartment building and started knocking on doors until someone came to help her. Her wound was not life threatening.

Police caught him because he was suspected of stealing beer from a nearby Circle K.

Munguia was convicted of second-degree assault and sentenced to a Washington juvenile justice facility for up to 2 1/2 years.