Isabella Guzman: The Case Of The Viral Teen Killer
Isabella Guzman made headlines in 2013 when the then-18-year-old stabbed her mother, 47-year-old Yun Mi Hoy, 79 times. Although the media portrayed Isabella Guzman as a killer, the case went in a new direction when Guzman claimed her mother had abused her for years leading up to the murder.
The Isabella Guzman case eventually went to trial, where Guzman pleaded not guilty by reason of insanity. Six years later, Guzman's story went viral on TikTok, bringing the story of her mother's murder back into the public spotlight and opening a conversation about the stigmas surrounding mental illness.
In the list below, we'll go back to 2013 and look at what led to Isabella Guzman committing such a violent crime against her mother.
In 2013, Isabella Guzman Was An 18-Year-Old Whom Her Family Described As A ‘Typical Teenager’
In August 2013, Isabella Guzman was 18 years old and living with her mother and stepfather in Aurora, CO, after dropping out of high school. Family members described the teenager as both “affectionate” and “loving.”
Following her mother's murder, reporters interviewed Guzman's aunt, Melanie Guzman, who described her niece as a normal teenager: “Her demeanor is pretty sweet. She’s very coquette. I can see her yelling, screaming and storming off and locking herself in her room and turning on her iPod.”
Melanie Guzman added that she couldn't imagine her niece becoming violent, and that there was “something more to it,” apparently referring to the police investigation.
Guzman Grew Increasingly Disrespectful Towards Her Mother, Yun Mi Hoy, Over Several Days
For years, Isabella Guzman's mother, Yun Mi Hoy, claimed her daughter was a difficult child. When Guzman was 7 years old, Hoy even sent her daughter to live with her biological father, Robert Guzman.
At the time of Hoy's murder, Guzman was living with her once again, but there was reportedly significant tension in the household. Guzman's stepfather, Ryan Hoy, later told the media that in the days leading up to his wife's murder, Guzman became “threatening” and “disrespectful” towards Yun Mi Hoy, and that the mother and daughter fought often.
Robert Guzman later said of his ex-wife, “She tried really, really hard for her family, but Isabella didn’t appreciate anything she did for her.”
Hoy Told Police About Her Daughter’s Threatening Behavior
On the afternoon of Wednesday, August 28, 2013, Yun Mi Hoy called police to report Guzman's threatening behavior, telling them she was afraid of her daughter. Police responded to the scene and reportedly informed Guzman that her mother had a right to kick her out of the house if she didn't abide by her mother and stepfather's rules.
Guzman's father later drove to Hoy's home to speak with his daughter. Robert Guzman later told the media, “I went to talk to Isabella, and we sat down in the backyard looking at the trees and the animals, and I started to talk to her about the respect that people should have for their parents.”
Robert stated that he thought the conversation had been productive, but he received a call only hours later that Guzman had murdered Hoy.
On August 28, 2013, Guzman’s Stepfather Found Her Standing Over Hoy’s Body Holding A Knife
Just before 10 pm on August 28, 2013, Ryan Hoy was at home when he heard a “thumping” sound coming from upstairs, as well as his wife's voice calling out his name.
Yun Mi Hoy had returned from working at the portrait studio she owned around 9:30 pm and gone upstairs to take a shower, but when Ryan Hoy reached the bathroom, he noticed blood seeping from under the door. Hoy claimed Guzman was holding the door shut, so at 10:05 pm, he ran back downstairs to call 911 and ask police to once again come to the family's home on the 2600 block of South Lima Street in Aurora, CO.
By the time police arrived at 10:16 pm, Yun Mi Hoy was dead, and Isabella Guzman was nowhere to be found.
Guzman Stabbed Her Mother 79 Times
When Ryan Hoy returned to the bathroom after calling 911, Guzman opened the door. Inside the bathroom, he reportedly saw Guzman holding a knife and covered in blood. Yun Mi Hoy was dead on the bathroom floor, and a baseball bat lay near her lifeless body.
According to an affidavit, Guzman “was just staring straight ahead when she walked past [Ryan Hoy].” She apparently said nothing to her stepfather before fleeing the home. Hoy also claimed he heard his wife, a Jehovah's Witness, shout “Jehovah” prior to Guzman opening the bathroom door.
Authorities pronounced Yun Mi Hoy dead at the scene after administering CPR, and an autopsy later revealed Guzman had stabbed her a total of 79 times: 31 wounds to the face and 48 to the neck.
Authorities Arrested Guzman The Following Day As She Was Leaving A Parking Garage
Photo: Aurora Police / Fair UseBefore police and medical personnel arrived at the scene, Isabella Guzman left her family home wearing only a pink sports bra and turquoise shorts. Police found her roughly 16 hours later; she had been hiding in an office building's parking garage located only a mile or so from the family home.
Police found Guzman after they received a call about someone seeing a body in a car. Upon police's arrival, they found the car empty, though Guzman had left some personal effects behind, including items tying her to Hoy's murder.
The search for Isabella Guzman came to a dramatic end around 2 pm on August 29, when three officers drew their weapons on her after seeing Guzman attempting to leave the parking garage. Guzman was taken into custody, where she was held without bail.
The Day Before Guzman Murdered Hoy, She Reportedly Emailed Her A Threatening Message
As investigators began collecting evidence related to Hoy's murder, more information came to light about the hours leading up to the killing. The day before, Tuesday, August 27, Ryan Hoy claimed Guzman spit in her mother's face. Guzman then wrote Hoy an email that said, among other things, "You will pay.”
Yun Mi Hoy didn't see the email until Wednesday morning, when she eventually decided to call police. After police left, Guzman reportedly went to her room for the rest of the afternoon.
Ryan Hoy later told authorities he had seen Guzman in the kitchen around 8:30 pm, only an hour before Hoy returned from work and Guzman attacked her.
Guzman Alleged Her Family Abused Her For Years
Following her arrest, Guzman told law enforcement her mother and stepfather had abused her for years leading up to the events of August 28, and that the pair were incredibly strict with her. Guzman stated, “My parents are Jehovah’s Witnesses, and I left the religion when I was 14, and the abuse at home worsened after I quit.”
In addition to the abuse Guzman allegedly endured while living with her mother, she also claimed an employee at the Colorado Mental Health Institute sexually assaulted her in a utility closet sometime in 2015. Guzman reported the assault at the time, but said there were two more incidents with the employee. Guzman later said that, “I was afraid that if I didn't do what he wanted that he could ruin my life.”
Doctors Claimed Guzman Was Schizophrenic And Experienced Delusions
In the summer of 2014, Isabella Guzman was put on trial for her mother's murder. She faced a first-degree murder charge, which could have resulted in the death penalty; however, doctors brought in as expert witnesses told the court Guzman was, in fact, schizophrenic and didn't believe her mother was her mother at the time of the murder.
One doctor described “disturbing” delusions Guzman had reportedly experienced for years and claimed she believed her mother was actually a woman named Cecilia, whom Guzman believed she had to kill in order to save the world.
Guzman's mental illness reportedly also accounted for her atypical behavior in court the day after murdering Yun Mi Hoy. In addition to refusing to leave her cell, which delayed court proceedings, Guzman smirked and made faces at camera crews once she entered the courtroom.
Guzman Was Found Not Guilty By Reason Of Insanity
Based on doctors' testimonies, the prosecutor for Guzman's case, 18th Judicial District Attorney George Brauchler, called for Guzman to be placed in a psychiatric facility.
Brauchler argued before the court that people convicted for crimes knew they did something wrong; however, Brauchler stated:
[In] this particular case, I am convinced, based on the evidence that I've seen and the information that's been presented in court, that this woman did not know right from wrong, and she could not have acted differently than she did, given the significant schizophrenia and paranoid delusions, audible, visual hallucinations that she was going through.
Guzman was subsequently found not guilty by reason of insanity and sent to the Colorado Mental Health Institute in Pueblo, CO.
In 2020, Guzman Requested Release From The Mental Hospital Where She Was Staying
Isabella Guzman's name resurfaced in the media in November 2020, when she requested release from the Colorado Mental Health Institute. Guzman, then 25, stated that at the time of her mother's murder, “I was not myself … and I have since been restored to full health.”
Guzman added that she was no longer a danger to herself or others, criteria that prosecutor George Brauchler had specified Guzman needed to meet when she was first sentenced to the psychiatric facility. Brauchler stipulated at the time that Guzman could spend days or the rest of her life in the hospital, depending on how much treatment she required.
In the summer of 2021, Guzman was eventually granted approval to leave the hospital in order to meet with her therapist. Prior to being granted partial release, Guzman said of killing her mother, "If I could change it or if I could take it back, I would."
Guzman’s Story Went Viral On TikTok In 2020
As news of Guzman's bid to be released from the Colorado Mental Health Institute surfaced in the media, her story went viral on TikTok. While some were sympathetic to Guzman's plight, other creators on the app played the 2013 court footage of Guzman glaring at camera crews in tandem with Eva Max's 2018 song “Sweet but Psycho,” which includes the lyrics, "Oh, she’s sweet but a psycho / A little bit psycho / At night she’s screamin’ / ‘I’m-ma-ma-ma out my mind.’”
The TikToks made about Guzman quickly became the source of much controversy, with many claiming the videos either romanticized or stigmatized mental illness. The reaction to the videos reportedly showed the deep divide in how the public perceived Isabella Guzman and her 2013 actions.
