Teen Said 'I'm Not a Psychopath.' Months Later, Police Say He Stabbed His Mother to Death

A Florida teen who police claim previously killed his father in self-defense is accused of murdering his mother after allegedly telling her, “I’m not a psychopath.” 

Collin Griffith, 17, was charged with murder in September 2024 after his mother, Catherine Griffith, was fatally stabbed in the neck in Polk County, Fla., according to a probable cause affidavit obtained by PEOPLE.

Police claim in the affidavit that Collin called 911 for help, saying that he and his mother had gotten into a fight and that she had fallen on a knife. Catherine was later pronounced dead.

The medical examiner, however, ruled that the injuries she suffered could not have been caused by falling onto a knife, according to the affidavit. Collin was subsequently indicted on murder and kidnapping charges and has pleaded not guilty.

Police say that Collin came to live with his mother in Florida following the shooting death of his father in 2023. The affidavit states that Collin was initially arrested in connection with his father’s death, but that evidence emerged that led investigators to believe it was self-defense and he was never convicted of a crime in connection.

In the affidavit, police allege that there had been a history of heated fights between Collin and Catherine and that he had previously been charged with domestic battery against his mother months before her death.

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In bodycam footage obtained and published by Fox 4, Collin is heard speaking to his grandmother as he sits in a police car following an arrest in November 2023.

“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 told his grandmother. “She kept telling me to shut up and shut up, and when I wouldn’t shut up, she hit me.”

The grandmother responds by disputing that he had ever said he wanted to coexist peacefully with Catherine.

The probable cause affidavit states that a year before his mother’s death, Collin allegedly told a police officer that he did not want to return home, saying he did not feel safe and that he would “kill myself or my mom.”