PEORIA, Arizona — A woman who used a claw hammer to beat her cousin to death and then attempted to clean the crime scene with a vacuum cleaner has been sentenced to more than two decades in prison.

Brianna Zerth, 33, was sentenced Friday to 21 years behind bars after pleading guilty to one count of domestic violence manslaughter in the death of her 33-year-old cousin, Peter McKenna Jr.

The killing occurred on May 4, 2022, at a home in Peoria. According to police reports and court records, Zerth and McKenna had been drinking late into the night when a violent argument broke out. Zerth later told investigators the details were “blurry,” claiming she woke up to discover McKenna dead on the floor in a large pool of blood.

However, the physical evidence told a much darker story. First responders found McKenna with multiple blunt-force trauma injuries consistent with being struck repeatedly by a hammer. Zerth reportedly covered his body with a jacket, tried to vacuum up the blood from the floor, and picked up broken glass so her young daughter wouldn’t step on it. She eventually called police, telling them McKenna was “stiff and cold to the touch.”

Zerth was initially charged with more serious offenses, including second-degree murder and tampering with evidence, but those charges were dropped as part of a plea agreement. She was credited with 1,056 days (nearly three years) already served while in custody.

The case drew significant attention due to the gruesome nature of the crime and Zerth’s alleged attempts to conceal it. Family members described the attack as particularly violent, and investigators noted the deliberate effort to clean the scene before contacting authorities.

During sentencing, the judge imposed the maximum term allowed for the manslaughter charge. Zerth will serve 21 years in prison. The plea deal spared her from facing life in prison on more serious murder charges.

The tragedy has left McKenna’s family devastated. Many are still struggling to understand how a night of drinking escalated into fatal violence. The case also highlights the dangers of alcohol-fueled domestic disputes and the long-term consequences for everyone involved.

As Zerth begins serving her sentence, the community continues to mourn Peter McKenna Jr., remembered by those who knew him as a kind individual whose life was cut short in a moment of rage.

This case serves as a grim reminder that domestic violence can escalate quickly, with devastating and irreversible results for families and communities.