Catherine Griffith Case: Oklahoma Shooting, Florida Trial, Verdict

By the time he was 17, Collin Griffith had killed both of his parents and been charged in neither death. Oklahoma prosecutors dropped a first-degree murder charge in the 2023 shooting of his father after concluding they could not rule out self-defense, and in February 2025 a Florida jury acquitted him of all charges in the stabbing death of his mother, Catherine Griffith. The Collin Griffith case became one of the more unusual homicide stories of the year in part because a second self-defense claim, from the same young defendant, succeeded in front of a jury.

The Oklahoma Shooting That Came First

On February 14, 2023, Collin fatally shot his father, Charles Griffith, at their home in Lincoln County, Oklahoma. In a 911 call, he told dispatchers his father had chased him into a bedroom with a knife during a physical fight, and that he grabbed a rifle and fired twice.¹

Collin was charged with first-degree murder. Less than a month later, Adam Panter, the District Attorney for Oklahoma’s 23rd District, dropped the charges. Panter said that after reviewing the available forensic and digital evidence, his office “could not rule out that Griffith acted in self-defense.” He also noted that Collin had invoked his right to counsel immediately, which kept investigators from getting a fuller statement beyond the 911 call. The case remained subject to reopening if new evidence surfaced.¹

The Eighteen Months Between the Two Deaths

After the Oklahoma case closed, Collin moved to Florida to live with his mother in Port Charlotte. The household drew steady attention from police, mental health responders, and the state’s child welfare agency.

In August 2023, Collin was placed under Florida’s Baker Act for mental health concerns. On release from a behavioral center, he reportedly told staff that if he was not kept there, he would “kill myself or I’ll kill my mother by shooting or stabbing her.”² A deputy had separately Baker Acted him after he threatened to kill his mother and grandmother.³

In November 2023, the Charlotte County Sheriff’s Office arrested Collin for domestic violence battery against Catherine. Sheriff Grady Judd said the fight began after Catherine took away Collin’s video game privileges, and that Collin pushed her down and stomped on her. He was placed on juvenile probation, and a no-contact order was entered barring him from contact with his mother.⁴

The Department of Children and Families was involved as well. Detective Lacey Venoniani later testified that DCF returned Collin to Catherine’s custody over the detective’s own view that “mother and son should not live together.” Venoniani said Catherine loved her son and was willing to “accept her fate” for the chance to be with him, while Collin had told her he would rather be in jail, a psychiatric facility, or foster care than live with his mother.⁵

The Night Catherine Griffith Died

On September 8, 2024, at about 6:00 p.m., Catherine drove from Port Charlotte to Auburndale to pick up Collin from the home of his grandmother, Susan Dethman. She was concerned that Collin was violating ongoing court orders.⁶

What happened in the roughly 90 minutes that followed became the central fight at trial. A neighbor, Nancy Jones, testified that within about 30 minutes of Catherine’s arrival she saw Collin arguing with his mother outside the home, grabbing her by the hair, and dragging her inside while Catherine pleaded with him to let go.⁷ Another neighbor said he heard Catherine say, “Stop, stop. You’re hurting me.”⁸

About an hour and 15 minutes after they went inside, Collin called 911. He told dispatchers he and his mother had gotten into a “very long fight” and that she had “lunged at him with a knife, and fell on it,” suffering a wound to her neck. When deputies and Polk County Fire Rescue arrived, Catherine was pronounced dead at the scene. Collin became “immediately uncooperative” and asked for a lawyer.⁷

An autopsy attributed her death to a deep penetrating knife wound to the neck, which the medical examiner found “inconsistent with an accidental injury.” Collin was charged with first-degree murder as a capital felony, kidnapping, and violation of a no-contact order. Sheriff Judd called him “a violent predator” who had “now killed both his father and his mother.”⁷

The Prosecution’s Case

Assistant State Attorney Mark Levine argued that Collin killed his mother out of hatred and to silence her, pointing to texts and recordings in which Catherine had accused him of murdering his father and threatened to expose what happened in Oklahoma. Levine framed the killing as “Operation kill mom accomplished” and told jurors it was premeditated, noting Collin’s history of threatening to kill Catherine by throwing her from a car, shooting her, or stabbing her, with stabbing a “reoccurring theme.”⁸

The medical examiner, Dr. David Garavan, testified that the wound was a large, gaping cut from a single blade that pierced Catherine’s esophagus, windpipe, and vocal cord. He classified the death as a homicide and said the wound was not consistent with someone falling on a knife. Investigators also observed that Collin had no defensive wounds on his hands.⁵

Catherine’s father, Robert Walantas, testified that months earlier Collin had told him: “My mom, I keep thinking over and over I want to slit her throat, I want her to bleed out, I want to smell the blood.”⁶ Corporal Joella Moore testified that Collin had told her about a second “persona” called “Collin 2” that “protects him and kills for him.”⁵

The Defense’s Case

Public defender Amy Thornhill argued Collin acted in self-defense against a mother she described as “violent and impulsive.” She presented evidence that Catherine had pulled a gun on Collin, threatened to shoot herself, and fabricated police reports against him, including a strangulation allegation.⁹ She told jurors Collin had repeatedly asked to be placed in foster care or a psychiatric facility because he “did not feel safe” with his mother and had been returned to her anyway.⁶

On the kidnapping count, Thornhill argued Catherine entered the home on her own after slamming a car door and making a scene in the carport, and that Collin had only touched her to move her inside and “avoid embarrassment.” She noted the lack of any scalp injury that would show hair-pulling, that Ring video did not capture a forced entry, and that the doors were unlocked. An AirPod the state cited as proof of a struggle, she said, had simply fallen out.⁸

In closing, Thornhill floated the theory that Catherine had “committed suicide by son,” asking the jury: “Isn’t it reasonable to believe that Cathy in her anger, her desperation to make Collin come home, picked up a knife and threatened him with it?”¹⁰

The most consequential defense witness was Catherine’s own mother. Susan Dethman testified about a history of violent and erratic behavior by her daughter, including beating Collin with a belt, forcing him into extreme physical exercises, and, on one occasion, handing him a gun with instructions to kill her. Dethman also said Catherine had a history of lying and had made “numerous” suicide attempts.¹¹³ She told the jury she did not believe her grandson murdered her daughter.⁵

The Verdict

On February 5, 2025, after less than 12 hours of deliberation, the jury found Collin Griffith not guilty on all counts. He was processed and released from jail.⁶⁵

The result left Catherine’s family split down the middle. Her father, Robert Walantas, had testified for the prosecution about his grandson’s graphic threats against her. Her mother, Susan Dethman, had testified for the defense and vouched for his innocence. At 17, Collin Griffith had killed both parents and walked away from both cases without a conviction.

1
ABC News. Teen Arrested in Mother Stabbing After Fatally Shooting Father
2
OKCFOX. Father Shot and Killed in Lincoln County
3
Scripps News. Collin Griffith Deadly Son Murder Trial
4
Good Morning America. Teen Arrested in Mother Stabbing After Fatally Shooting Father
5
Court TV. Collin Griffith Deadly Son Murder Trial
6
ABC 7 Chicago. Florida Teen Collin Griffith Found Not Guilty of Killing Mom
7
Polk County Sheriff’s Office. Polk County Sheriff’s Office Arrests 17-Year-Old for Murdering His Mother
8
Yahoo News. Heated Fight, Mother Dead
9
The Ledger. Differing Tales Offered of Mother’s Death in Collin Griffith Murder Trial
10
People. Florida Teen Killed Dad in Self-Defense, Acquitted of Killing Mother
11
Court TV. Collin Griffith’s Grandmother Says Victim Had History of Lying