‘I want to slit her throat’: Mom allegedly stabbed to death by son threatened to share proof that he murdered his father, lawyers say

Colin Griffith sits with his defense attorney Howard Dimmig

Collin Griffith sits with his defense attorney Howard Dimmig during opening statements (Law&Crime/YouTube).

The trial of a Florida teen who allegedly stabbed his mother in September following a fight kicked off presented two very different versions of what occurred on the day of the violent altercation in opening statements.

Collin Griffith, 17, showed no emotion as he sat with his defense team, attorneys Amy Thornhill and Howard Dimmig, while prosecutor Mark Levine outlined the “carnage” that took place on the afternoon of Sept. 8, 2024 and the events leading up to the day Catherine Griffith, 39, lost her life, allegedly at the hands of her own teenage son.

In front of Florida’s 10th Circuit Judge Kevin Abdoney, Levine and Thornhill both painted a picture of a troubled household that had been rocked over a year earlier when Collin shot and killed his father in Oklahoma, apparently in self-defense.

Levine went into detail about several attempts made by Cathy Griffith to connect with her teenage son after he came to live with her following the Feb. 14, 2023 death of his father, Charles Griffith, Cathy Griffith’s ex-husband. As the single mother tried to “make up for lost time” with her son after moving him from Oklahoma to her home in Florida, he rebuffed her as she asked him to either spend time with her or help around the house. According to Levine, Cathy Griffith not only provided for her son, but made it so he wanted for nothing, gifting him with various devices and items including video games, a computer, a car, a phone, and more.

But when asked to do his part in maintaining a clean household, including taking out garbage from his bedroom where ants had begun to gather, Collin reportedly “didn’t want to be bothered.”

Eventually, mother and son began to clash, Levine said. Their verbal arguments first culminated in a physical altercation in November 2023, during which Collin “attacked” and “stomped” his mother. He was arrested and booked into jail, but was released the following day.

It was then, Levine said, that Collin allegedly began making threats against his mother. The prosecutor said that Collin told his maternal grandfather, “More than anything else, I want to slit her throat and feel her bleed out, and feel the life leave her body. That’s how much I hate her.”

Levine described how their relationship deteriorated as Cathy Griffith’s final day approached. The increasingly frustrated mother started giving her son “ultimatums” in exchange for his compliance regarding household chores.

Levine described a text that Cathy Griffith sent to her son between 12:00 and 12:29 p.m. the day of her death, which read as follows:

Collin, the recordings of you admitting to killing [your father] and planning the murder, there are four different instances from my Ring camera, are all going to Bob, Susie, Amanda, and Chris at 3 p.m. today. … Plus the recovered audio from Chuck’s iCloud where you told your dad you hated me and I was an evil bitch are being sent too. My dad is sending me his recordings of you telling him how you planned my murder back in February. … All because you didn’t want to help me mount a bookshelf.

Levine said that Cathy Griffith threatened to send the recordings unless he called her back — and just hours later, she was dead from a stab wound to her neck.

“You will see, firsthand, the carnage that Cathy suffered,” Levine told the jury.

When Thornhill took to the podium, however, she promised a very different story. She said that Cathy Griffith was reportedly often estranged from members of her family and instigated fights, had a drinking problem and a pill problem, and attempted to commit suicide several times.

“Cathy has threatened or done harm to other people,” Thornhill said — including threatening her own son.

Cathy Griffith owned a gun and lied about it, Thornhill said. The boy’s defense lawyer described an instance during which Collin told police that Cathy Griffith handed Collin an envelope saying it contained “all the important papers you’ll need if I’m gone.” She then pointed her gun at her son and said that “she was either going to shoot him or herself or both.” And then she gave her son the gun and told him to “just shoot me.”

Collin reported the incident to school officials, who called the police. When officers showed up to talk to Cathy Griffith, however, she denied it ever happened, Thornhill said. In the end, the lawyer said, the police believed the mother and not the son.

According to Thornhill, Cathy Griffith also reportedly defied medical advice when it came to medications for her son and inpatient treatment.

Thornhill seemed to set up another self-defense scenario, saying that Collin made repeated statements that he didn’t feel safe with his mother. He reportedly said when he was going to be returned to his mother’s custody after the November 2023 domestic violence incident that he would defend himself if he had to, and that he would rather be put in foster care than live with his mother. Collin told police that he was “scared” of his mom, and that she threatened to kick him out of the house.

Cathy Griffith, as the defense portrayed her, was a violent, erratic woman who waved a gun at her son and threatened to harm herself and him. Thornhill claimed that Cathy Griffith punished Collin by making him do pushups, hold weights above his head, and “whipped him with a belt” in front of her mother.

During the November 2023 incident, Cathy Griffith reportedly hit Collin in the face, which prompted him to do a “wrestling move” on his mother and hit her back.

Collin was put in jail. When his mom came to pick him up, he told police that he was afraid to get in the car with her, Thornhill said. Police “forced” him to ride home with her, and she made him do “marches with weights above his head,” apparently seen on an officer’s body worn camera.

Thornhill said that both mother and son had been “Baker Acted,” citing Florida’s law that involuntarily commits someone to a mental health facility if they appear to be having a crisis.

“All is not well at home, clearly,” she said.

On the day Cathy Griffith died, Thornhill portrayed Collin as the one who tearfully called 911 and tried to save his mother’s life, that “his mom came to him, went into the house where he was safe and attacked him, and he had to defend himself.”

According to police who arrived upon the bloody scene on Sept. 8, however, Collin was “calm, cool, collected — and he had blood on him.”

Polk County Sheriff Grady Judd said during a press conference that right after Cathy Griffith’s death, Collin “looked the deputy in the eye and said: ‘I know my rights. I want an attorney.””

Judd also said that Griffith showed “zero remorse.”