A troubled woman accused of a shocking knife attack on a California tourist inside Macy’s flagship Manhattan store confessed her real motive to police: she wanted prison—not another stretch in a psychiatric institution, prosecutors alleged on Wednesday.

Kerri Aherne, 43, is at the center of a harrowing case after she allegedly plunged a kitchen knife into a 39-year-old mother’s back as the visitor changed her baby’s diaper in the legendary Herald Square department store on December 12, 2025. The midday horror left New York shoppers stunned and the victim—and her 10-month-old daughter—reeling from the random violence.

Aherne—described as a transient and ex-home health aide from Massachusetts—grabbed a cab from her bed at the Manhattan Psychiatric Center’s transitional housing, then walked into Macy’s, purchased a hefty kitchen knife, and made a beeline for the seventh-floor restroom. That’s where, prosecutors say, the voices in her head told her to find someone to kill—or else be killed herself.

“She told officers that she’d rather face time behind bars than endure the torment of hospitals again,” Assistant District Attorney Paul Barker told the Manhattan Supreme Court during Aherne’s appearance before Judge Ann Thompson. In court, Aherne appeared in a pink sweatshirt and gray sweatpants and pleaded not guilty to attempted murder, assault, and child endangerment. But it was her eerie admission—allegedly made right after her arrest—that rattled the courtroom: jail was preferable to psychiatric care.

On the day of the rampage, the unsuspecting victim was tending to her infant when Aherne allegedly struck from behind. Security quickly nabbed the accused attacker. Aherne later told The Post in a jailhouse interview that she couldn’t bear another hospital stay.

Prosecutors said Aherne has a history of mental health struggles and had recently spent a year committed for treatment. Given the circumstances of the violent ambush, Judge Thompson ordered her held without bail pending a psychological evaluation, with her next hearing set for February 11.

If convicted on the top charge, Aherne could face up to 25 years behind bars for the brutal Macy’s attack that left a tourist family’s visit in tatters.