A Florida teen who authorities say k*illed his father in self-defense in 2023 has been found not guilty of murdering his mother — after again claiming self-defense.
Collin Griffith, 17, was charged with murder after his mother, Catherine Griffith, was fatally stabbed in the neck at his grandmother’s home in Polk County, Fla. in September 2024, according to a probable cause affidavit.
In the affidavit, police claimed that Collin called 911, saying that he and his mother had gotten into a fight and that she had fallen on a knife. But after a medical examiner ruled that Catherine’s injuries could not have been caused by falling on a knife, Collin was charged with murder and kidnapping.
During his trial, Collin’s attorney argued that he had acted in self-defense during the incident and that there was no evidence Catherine was in the home of her mother, Susan Detman, against her will.
Detman testified during the trial that her daughter was unpredictable and that she had seen her be violent toward Collin. Amy Porinchak Thornhill, Collin’s attorney, claimed that Catherine had even once pointed a gun at her son.
During closing arguments, Thornhill claimed the prosecution had no proof of what happened inside the home on the day Catherine was kil*led and that Collin had previously been trying to get away from his mother.
“Isn’t it reasonable to believe that Cathy in her anger, her desperation to make Collin come home, that she picked up a knife and threatened him with it?,” Thornhill said, before claiming that it was reasonable to believe she wanted to die by “suicide by son.”
Collin was ultimately acquitted of murder and kidnapping, according to reports.
Police said in the affidavit that Collin had come to live with his mother in 2023 following the de*ath of his father, whom Collin fatally shot.
Collin was initially arrested in connection with his father’s de*ath, per the affidavit, but evidence would emerge that led authorities to believe it was self-defense. Collin was never convicted of a crime in connection with his father’s de*ath.
Collin and Catherine, meanwhile, had a history of heated fights, according to the affidavit, and he had previously been charged with domestic battery against her months before her de*ath.
“I was saying, ‘Mom, I’m not a psychopath. I’m not this murderer. I’m just trying to peacefully leave or peacefully coexist,’” he reportedly said to his grandmother. “She kept telling me to shut up and shut up, and when I wouldn’t shut up, she hit me.”
The affidavit claims that a year before Catherine’s death, Collin allegedly told police that he did not want to return home, saying he did not feel safe and that he would “ki*ll myself or my mom.”
